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   1This is groff, produced by makeinfo version 4.8 from ./groff.texinfo.
   2
   3   This manual documents GNU `troff' version 1.19.2.
   4
   5   Copyright (C) 1994-2000, 2001, 2002, 2003, 2004, 2005 Free Software
   6Foundation, Inc.
   7
   8     Permission is granted to copy, distribute and/or modify this
   9     document under the terms of the GNU Free Documentation License,
  10     Version 1.1 or any later version published by the Free Software
  11     Foundation; with no Invariant Sections, with the Front-Cover texts
  12     being `A GNU Manual," and with the Back-Cover Texts as in (a)
  13     below.  A copy of the license is included in the section entitled
  14     `GNU Free Documentation License."
  15
  16     (a) The FSF's Back-Cover Text is: `You have freedom to copy and
  17     modify this GNU Manual, like GNU software.  Copies published by
  18     the Free Software Foundation raise funds for GNU development."
  19
  20INFO-DIR-SECTION Typesetting
  21START-INFO-DIR-ENTRY
  22* Groff: (groff).               The GNU troff document formatting system.
  23END-INFO-DIR-ENTRY
  24
  25
  26File: groff,  Node: Drawing Requests,  Next: Traps,  Prev: Page Motions,  Up: gtroff Reference
  27
  285.23 Drawing Requests
  29=====================
  30
  31`gtroff' provides a number of ways to draw lines and other figures on
  32the page.  Used in combination with the page motion commands (see *Note
  33Page Motions::, for more info), a wide variety of figures can be drawn.
  34However, for complex drawings these operations can be quite
  35cumbersome, and it may be wise to use graphic preprocessors like `gpic'
  36or `ggrn'.  *Note gpic::, and *Note ggrn::, for more information.
  37
  38   All drawing is done via escapes.
  39
  40 -- Escape: \l'l'
  41 -- Escape: \l'lg'
  42     Draw a line horizontally.  L is the length of the line to be
  43     drawn.  If it is positive, start the line at the current location
  44     and draw to the right; its end point is the new current location.
  45     Negative values are handled differently: The line starts at the
  46     current location and draws to the left, but the current location
  47     doesn't move.
  48
  49     L can also be specified absolutely (i.e. with a leading `|') which
  50     draws back to the beginning of the input line.  Default scaling
  51     indicator is `m'.
  52
  53     The optional second parameter G is a glyph to draw the line with.
  54     If this second argument is not specified, `gtroff' uses the
  55     underscore glyph, `\[ru]'.
  56
  57     To separate the two arguments (to prevent `gtroff' from
  58     interpreting a drawing glyph as a scaling indicator if the glyph is
  59     represented by a single character) use `\&'.
  60
  61     Here a small useful example:
  62
  63
  64          .de box
  65          \[br]\\$*\[br]\l'|0\[rn]'\l'|0\[ul]'
  66          ..
  67
  68     Note that this works by outputting a box rule (a vertical line),
  69     then the text given as an argument and then another box rule.
  70     Finally, the line drawing escapes both draw from the current
  71     location to the beginning of the _input_ line - this works because
  72     the line length is negative, not moving the current point.
  73
  74 -- Escape: \L'l'
  75 -- Escape: \L'lg'
  76     Draw vertical lines.  Its parameters are similar to the `\l'
  77     escape, except that the default scaling indicator is `v'.  The
  78     movement is downwards for positive values, and upwards for
  79     negative values.  The default glyph is the box rule glyph,
  80     `\[br]'.  As with the vertical motion escapes, text processing
  81     blindly continues where the line ends.
  82
  83
  84          This is a \L'3v'test.
  85
  86     Here the result, produced with `grotty'.
  87
  88
  89          This is a
  90                    |
  91                    |
  92                    |test.
  93
  94
  95 -- Escape: \D'command arg ...'
  96     The `\D' escape provides a variety of drawing functions.  Note
  97     that on character devices, only vertical and horizontal lines are
  98     supported within `grotty'; other devices may only support a subset
  99     of the available drawing functions.
 100
 101     The default scaling indicator for all subcommands of `\D' is `m'
 102     for horizontal distances and `v' for vertical ones.  Exceptions
 103     are `\D'f ...'' and `\D't ...'' which use `u' as the default, and
 104     `\D'FX ...'' which arguments are treated similar to the `defcolor'
 105     request.
 106
 107    `\D'l DX DY''
 108          Draw a line from the current location to the relative point
 109          specified by (DX,DY), where positive values mean down and
 110          right, respectively.  The end point of the line is the new
 111          current location.
 112
 113          The following example is a macro for creating a box around a
 114          text string; for simplicity, the box margin is taken as a
 115          fixed value, 0.2m.
 116
 117
 118               .de BOX
 119               .  nr @wd \w'\\$1'
 120               \h'.2m'\
 121               \h'-.2m'\v'(.2m - \\n[rsb]u)'\
 122               \D'l 0 -(\\n[rst]u - \\n[rsb]u + .4m)'\
 123               \D'l (\\n[@wd]u + .4m) 0'\
 124               \D'l 0 (\\n[rst]u - \\n[rsb]u + .4m)'\
 125               \D'l -(\\n[@wd]u + .4m) 0'\
 126               \h'.2m'\v'-(.2m - \\n[rsb]u)'\
 127               \\$1\
 128               \h'.2m'
 129               ..
 130
 131          First, the width of the string is stored in register `@wd'.
 132          Then, four lines are drawn to form a box, properly offset by
 133          the box margin.  The registers `rst' and `rsb' are set by the
 134          `\w' escape, containing the largest height and depth of the
 135          whole string.
 136
 137    `\D'c D''
 138          Draw a circle with a diameter of D with the leftmost point at
 139          the current position.  After drawing, the current location is
 140          positioned at the rightmost point of the circle.
 141
 142    `\D'C D''
 143          Draw a solid circle with the same parameters and behaviour as
 144          an outlined circle.  No outline is drawn.
 145
 146    `\D'e X Y''
 147          Draw an ellipse with a horizontal diameter of X and a vertical
 148          diameter of Y with the leftmost point at the current position.
 149          After drawing, the current location is positioned at the
 150          rightmost point of the ellipse.
 151
 152    `\D'E X Y''
 153          Draw a solid ellipse with the same parameters and behaviour
 154          as an outlined ellipse.  No outline is drawn.
 155
 156    `\D'a DX1 DY1 DX2 DY2''
 157          Draw an arc clockwise from the current location through the
 158          two specified relative locations (DX1,DY1) and (DX2,DY2).
 159          The coordinates of the first point are relative to the
 160          current position, and the coordinates of the second point are
 161          relative to the first point.  After drawing, the current
 162          position is moved to the final point of the arc.
 163
 164    `\D'~ DX1 DY1 DX2 DY2 ...''
 165          Draw a spline from the current location to the relative point
 166          (DX1,DY1) and then to (DX2,DY2), and so on.  The current
 167          position is moved to the terminal point of the drawn curve.
 168
 169    `\D'f N''
 170          Set the shade of gray to be used for filling solid objects
 171          to N; N must be an integer between 0 and 1000, where 0
 172          corresponds solid white and 1000 to solid black, and values
 173          in between correspond to intermediate shades of gray.  This
 174          applies only to solid circles, solid ellipses, and solid
 175          polygons.  By default, a level of 1000 is used.
 176
 177          Despite of being silly, the current point is moved
 178          horizontally to the right by N.
 179
 180          Don't use this command!  It has the serious drawback that it
 181          will be always rounded to the next integer multiple of the
 182          horizontal resolution (the value of the `hor' keyword in the
 183          `DESC' file).  Use `\M' (*note Colors::) or `\D'Fg ...''
 184          instead.
 185
 186    `\D'p DX1 DY1 DX2 DY2 ...''
 187          Draw a polygon from the current location to the relative
 188          position (DX1,DY1) and then to (DX2,DY2) and so on.  When the
 189          specified data points are exhausted, a line is drawn back to
 190          the starting point.  The current position is changed by
 191          adding the sum of all arguments with odd index to the actual
 192          horizontal position and the even ones to the vertical
 193          position.
 194
 195    `\D'P DX1 DY1 DX2 DY2 ...''
 196          Draw a solid polygon with the same parameters and behaviour
 197          as an outlined polygon.  No outline is drawn.
 198
 199          Here a better variant of the box macro to fill the box with
 200          some color.  Note that the box must be drawn before the text
 201          since colors in `gtroff' are not transparent; the filled
 202          polygon would hide the text completely.
 203
 204
 205               .de BOX
 206               .  nr @wd \w'\\$1'
 207               \h'.2m'\
 208               \h'-.2m'\v'(.2m - \\n[rsb]u)'\
 209               \M[lightcyan]\
 210               \D'P 0 -(\\n[rst]u - \\n[rsb]u + .4m) \
 211                    (\\n[@wd]u + .4m) 0 \
 212                    0 (\\n[rst]u - \\n[rsb]u + .4m) \
 213                    -(\\n[@wd]u + .4m) 0'\
 214               \h'.2m'\v'-(.2m - \\n[rsb]u)'\
 215               \M[]\
 216               \\$1\
 217               \h'.2m'
 218               ..
 219
 220    `\D't N''
 221          Set the current line thickness to N machine units.  A value of
 222          zero selects the smallest available line thickness.  A
 223          negative value makes the line thickness proportional to the
 224          current point size (this is the default behaviour of AT&T
 225          `troff').
 226
 227          Despite of being silly, the current point is moved
 228          horizontally to the right by N.
 229
 230    `\D'FSCHEME COLOR_COMPONENTS''
 231          Change current fill color.  SCHEME is a single letter
 232          denoting the color scheme: `r' (rgb), `c' (cmy), `k' (cmyk),
 233          `g' (gray), or `d' (default color).  The color components use
 234          exactly the same syntax as in the `defcolor' request (*note
 235          Colors::); the command `\D'Fd'' doesn't take an argument.
 236
 237          _No_ position changing!
 238
 239          Examples:
 240
 241
 242          \D'Fg .3'      \" same gray as \D'f 700' \D'Fr #0000ff' \"
 243          blue
 244
 245   *Note Graphics Commands::.
 246
 247 -- Escape: \b'string'
 248     "Pile" a sequence of glyphs vertically, and center it vertically
 249     on the current line.  Use it to build large brackets and braces.
 250
 251     Here an example how to create a large opening brace:
 252
 253
 254          \b'\[lt]\[bv]\[lk]\[bv]\[lb]'
 255
 256     The first glyph is on the top, the last glyph in STRING is at the
 257     bottom.  Note that `gtroff' separates the glyphs vertically by 1m,
 258     and the whole object is centered 0.5m above the current baseline;
 259     the largest glyph width is used as the width for the whole object.
 260     This rather unflexible positioning algorithm doesn't work with
 261     `-Tdvi' since the bracket pieces vary in height for this device.
 262     Instead, use the `eqn' preprocessor.
 263
 264     *Note Manipulating Spacing::, how to adjust the vertical spacing
 265     with the `\x' escape.
 266
 267
 268File: groff,  Node: Traps,  Next: Diversions,  Prev: Drawing Requests,  Up: gtroff Reference
 269
 2705.24 Traps
 271==========
 272
 273"Traps" are locations, which, when reached, call a specified macro.
 274These traps can occur at a given location on the page, at a given
 275location in the current diversion, at a blank line, after a certain
 276number of input lines, or at the end of input.
 277
 278   Setting a trap is also called "planting".  It is also said that a
 279trap is "sprung" if the associated macro is executed.
 280
 281* Menu:
 282
 283* Page Location Traps::
 284* Diversion Traps::
 285* Input Line Traps::
 286* Blank Line Traps::
 287* End-of-input Traps::
 288
 289
 290File: groff,  Node: Page Location Traps,  Next: Diversion Traps,  Prev: Traps,  Up: Traps
 291
 2925.24.1 Page Location Traps
 293--------------------------
 294
 295"Page location traps" perform an action when `gtroff' reaches or passes
 296a certain vertical location on the page.  Page location traps have a
 297variety of purposes, including:
 298
 299   * setting headers and footers
 300
 301   * setting body text in multiple columns
 302
 303   * setting footnotes
 304
 305 -- Request: .vpt flag
 306 -- Register: \n[.vpt]
 307     Enable vertical position traps if FLAG is non-zero, or disables
 308     them otherwise.  Vertical position traps are traps set by the `wh'
 309     or `dt' requests.  Traps set by the `it' request are not vertical
 310     position traps.  The parameter that controls whether vertical
 311     position traps are enabled is global.  Initially vertical position
 312     traps are enabled.  The current setting of this is available in the
 313     `.vpt' read-only number register.
 314
 315     Note that a page can't be ejected if `vpt' is set to zero.
 316
 317 -- Request: .wh dist [macro]
 318     Set a page location trap.  Non-negative values for DIST set the
 319     trap relative to the top of the page; negative values set the trap
 320     relative to the bottom of the page.  Default scaling indicator is
 321     `v'.
 322
 323     MACRO is the name of the macro to execute when the trap is sprung.
 324     If MACRO is missing, remove the first trap (if any) at DIST.
 325
 326     The following is a simple example of how many macro packages set
 327     headers and footers.
 328
 329
 330          .de hd                \" Page header
 331          '  sp .5i
 332          .  tl 'Title''date'
 333          '  sp .3i
 334          ..
 335          .
 336          .de fo                \" Page footer
 337          '  sp 1v
 338          .  tl ''%''
 339          '  bp
 340          ..
 341          .
 342          .wh 0   hd            \" trap at top of the page
 343          .wh -1i fo            \" trap one inch from bottom
 344
 345     A trap at or below the bottom of the page is ignored; it can be
 346     made active by either moving it up or increasing the page length
 347     so that the trap is on the page.
 348
 349     It is possible to have more than one trap at the same location; to
 350     do so, the traps must be defined at different locations, then
 351     moved together with the `ch' request; otherwise the second trap
 352     would replace the first one.  Earlier defined traps hide later
 353     defined traps if moved to the same position (the many empty lines
 354     caused by the `bp' request are omitted in the following example):
 355
 356
 357          .de a
 358          .  nop a
 359          ..
 360          .de b
 361          .  nop b
 362          ..
 363          .de c
 364          .  nop c
 365          ..
 366          .
 367          .wh 1i a
 368          .wh 2i b
 369          .wh 3i c
 370          .bp
 371              => a b c
 372
 373
 374          .ch b 1i
 375          .ch c 1i
 376          .bp
 377              => a
 378
 379
 380          .ch a 0.5i
 381          .bp
 382              => a b
 383
 384
 385 -- Register: \n[.t]
 386     A read-only number register holding the distance to the next trap.
 387
 388     If there are no traps between the current position and the bottom
 389     of the page, it contains the distance to the page bottom.  In a
 390     diversion, the distance to the page bottom is infinite (the
 391     returned value is the biggest integer which can be represented in
 392     `groff') if there are no diversion traps.
 393
 394 -- Request: .ch macro [dist]
 395     Change the location of a trap.  The first argument is the name of
 396     the macro to be invoked at the trap, and the second argument is
 397     the new location for the trap (note that the parameters are
 398     specified in opposite order as in the `wh' request).  This is
 399     useful for building up footnotes in a diversion to allow more
 400     space at the bottom of the page for them.
 401
 402     Default scaling indicator for DIST is `v'.  If DIST is missing,
 403     the trap is removed.
 404
 405
 406 -- Register: \n[.ne]
 407     The read-only number register `.ne' contains the amount of space
 408     that was needed in the last `ne' request that caused a trap to be
 409     sprung.  Useful in conjunction with the `.trunc' register.  *Note
 410     Page Control::, for more information.
 411
 412     Since the `.ne' register is only set by traps it doesn't make much
 413     sense to use it outside of trap macros.
 414
 415 -- Register: \n[.trunc]
 416     A read-only register containing the amount of vertical space
 417     truncated by the most recently sprung vertical position trap, or,
 418     if the trap was sprung by an `ne' request, minus the amount of
 419     vertical motion produced by the `ne' request.  In other words, at
 420     the point a trap is sprung, it represents the difference of what
 421     the vertical position would have been but for the trap, and what
 422     the vertical position actually is.
 423
 424     Since the `.trunc' register is only set by traps it doesn't make
 425     much sense to use it outside of trap macros.
 426
 427 -- Register: \n[.pe]
 428     A read-only register which is set to 1 while a page is ejected with
 429     the `bp' request (or by the end of input).
 430
 431     Outside of traps this register is always zero.  In the following
 432     example, only the second call to `x' is caused by `bp'.
 433
 434
 435          .de x
 436          \&.pe=\\n[.pe]
 437          .br
 438          ..
 439          .wh 1v x
 440          .wh 4v x
 441          A line.
 442          .br
 443          Another line.
 444          .br
 445              => A line.
 446                 .pe=0
 447                 Another line.
 448
 449                 .pe=1
 450
 451
 452   An important fact to consider while designing macros is that
 453diversions and traps do not interact normally.  For example, if a trap
 454invokes a header macro (while outputting a diversion) which tries to
 455change the font on the current page, the effect will not be visible
 456before the diversion has completely been printed (except for input
 457protected with `\!' or `\?') since the data in the diversion is already
 458formatted.  In most cases, this is not the expected behaviour.
 459
 460
 461File: groff,  Node: Diversion Traps,  Next: Input Line Traps,  Prev: Page Location Traps,  Up: Traps
 462
 4635.24.2 Diversion Traps
 464----------------------
 465
 466 -- Request: .dt [dist macro]
 467     Set a trap _within_ a diversion.  DIST is the location of the trap
 468     (identical to the `wh' request; default scaling indicator is `v')
 469     and MACRO is the name of the macro to be invoked.  If called
 470     without arguments, the diversion trap is removed.
 471
 472     Note that there exists only a single diversion trap.
 473
 474     The number register `.t' still works within diversions.  *Note
 475     Diversions::, for more information.
 476
 477
 478File: groff,  Node: Input Line Traps,  Next: Blank Line Traps,  Prev: Diversion Traps,  Up: Traps
 479
 4805.24.3 Input Line Traps
 481-----------------------
 482
 483 -- Request: .it n macro
 484 -- Request: .itc n macro
 485     Set an input line trap.  N is the number of lines of input which
 486     may be read before springing the trap, MACRO is the macro to be
 487     invoked.  Request lines are not counted as input lines.
 488
 489     For example, one possible use is to have a macro which prints the
 490     next N lines in a bold font.
 491
 492
 493          .de B
 494          .  it \\$1 B-end
 495          .  ft B
 496          ..
 497          .
 498          .de B-end
 499          .  ft R
 500          ..
 501
 502     The `itc' request is identical except that an interrupted text
 503     line (ending with `\c') is not counted as a separate line.
 504
 505     Both requests are associated with the current environment (*note
 506     Environments::); switching to another environment disables the
 507     current input trap, and going back reactivates it, restoring the
 508     number of already processed lines.
 509
 510
 511File: groff,  Node: Blank Line Traps,  Next: End-of-input Traps,  Prev: Input Line Traps,  Up: Traps
 512
 5135.24.4 Blank Line Traps
 514-----------------------
 515
 516 -- Request: .blm macro
 517     Set a blank line trap.  `gtroff' executes MACRO when it encounters
 518     a blank line in the input file.
 519
 520
 521File: groff,  Node: End-of-input Traps,  Prev: Blank Line Traps,  Up: Traps
 522
 5235.24.5 End-of-input Traps
 524-------------------------
 525
 526 -- Request: .em macro
 527     Set a trap at the end of input.  MACRO is executed after the last
 528     line of the input file has been processed.
 529
 530     For example, if the document had to have a section at the bottom
 531     of the last page for someone to approve it, the `em' request could
 532     be used.
 533
 534
 535          .de approval
 536          .  ne 5v
 537          .  sp |(\\n[.t] - 6v)
 538          .  in +4i
 539          .  lc _
 540          .  br
 541          Approved:\t\a
 542          .  sp
 543          Date:\t\t\a
 544          ..
 545          .
 546          .em approval
 547
 548
 549
 550File: groff,  Node: Diversions,  Next: Environments,  Prev: Traps,  Up: gtroff Reference
 551
 5525.25 Diversions
 553===============
 554
 555In `gtroff' it is possible to "divert" text into a named storage area.
 556Due to the similarity to defining macros it is sometimes said to be
 557stored in a macro.  This is used for saving text for output at a later
 558time, which is useful for keeping blocks of text on the same page,
 559footnotes, tables of contents, and indices.
 560
 561   For orthogonality it is said that `gtroff' is in the "top-level
 562diversion" if no diversion is active (i.e., the data is diverted to the
 563output device).
 564
 565 -- Request: .di macro
 566 -- Request: .da macro
 567     Begin a diversion.  Like the `de' request, it takes an argument of
 568     a macro name to divert subsequent text into.  The `da' macro
 569     appends to an existing diversion.
 570
 571     `di' or `da' without an argument ends the diversion.
 572
 573 -- Request: .box macro
 574 -- Request: .boxa macro
 575     Begin (or appends to) a diversion like the `di' and `da' requests.
 576     The difference is that `box' and `boxa' do not include a
 577     partially-filled line in the diversion.
 578
 579     Compare this:
 580
 581
 582          Before the box.
 583          .box xxx
 584          In the box.
 585          .br
 586          .box
 587          After the box.
 588          .br
 589              => Before the box.  After the box.
 590          .xxx
 591              => In the box.
 592
 593     with this:
 594
 595
 596          Before the diversion.
 597          .di yyy
 598          In the diversion.
 599          .br
 600          .di
 601          After the diversion.
 602          .br
 603              => After the diversion.
 604          .yyy
 605              => Before the diversion.  In the diversion.
 606
 607     `box' or `boxa' without an argument ends the diversion.
 608
 609 -- Register: \n[.z]
 610 -- Register: \n[.d]
 611     Diversions may be nested.  The read-only number register `.z'
 612     contains the name of the current diversion (this is a string-valued
 613     register).  The read-only number register `.d' contains the current
 614     vertical place in the diversion.  If not in a diversion it is the
 615     same as register `nl'.
 616
 617 -- Register: \n[.h]
 618     The "high-water mark" on the current page.  It corresponds to the
 619     text baseline of the lowest line on the page.  This is a read-only
 620     register.
 621
 622
 623          .tm .h==\n[.h], nl==\n[nl]
 624              => .h==0, nl==-1
 625          This is a test.
 626          .br
 627          .sp 2
 628          .tm .h==\n[.h], nl==\n[nl]
 629              => .h==40, nl==120
 630
 631     As can be seen in the previous example, empty lines are not
 632     considered in the return value of the `.h' register.
 633
 634 -- Register: \n[dn]
 635 -- Register: \n[dl]
 636     After completing a diversion, the read-write number registers `dn'
 637     and `dl' contain the vertical and horizontal size of the diversion.
 638     Note that only the just processed lines are counted: For the
 639     computation of `dn' and `dl', the requests `da' and `boxa' are
 640     handled as if `di' and `box' had been used - lines which have been
 641     already stored in a macro are not taken into account.
 642
 643
 644          .\" Center text both horizontally & vertically
 645          .
 646          .\" Enclose macro definitions in .eo and .ec
 647          .\" to avoid the doubling of the backslash
 648          .eo
 649          .\" macro .(c starts centering mode
 650          .de (c
 651          .  br
 652          .  ev (c
 653          .  evc 0
 654          .  in 0
 655          .  nf
 656          .  di @c
 657          ..
 658
 659
 660          .\" macro .)c terminates centering mode
 661          .de )c
 662          .  br
 663          .  ev
 664          .  di
 665          .  nr @s (((\n[.t]u - \n[dn]u) / 2u) - 1v)
 666          .  sp \n[@s]u
 667          .  ce 1000
 668          .  @c
 669          .  ce 0
 670          .  sp \n[@s]u
 671          .  br
 672          .  fi
 673          .  rr @s
 674          .  rm @s
 675          .  rm @c
 676          ..
 677          .\" End of macro definitions, restore escape mechanism
 678          .ec
 679
 680
 681 -- Escape: \!
 682 -- Escape: \?anything\?
 683     Prevent requests, macros, and escapes from being interpreted when
 684     read into a diversion.  Both escapes take the given text and
 685     "transparently" embed it into the diversion.  This is useful for
 686     macros which shouldn't be invoked until the diverted text is
 687     actually output.
 688
 689     The `\!' escape transparently embeds text up to and including the
 690     end of the line.  The `\?' escape transparently embeds text until
 691     the next occurrence of the `\?' escape.  Example:
 692
 693
 694          \?ANYTHING\?
 695
 696     ANYTHING may not contain newlines; use `\!'  to embed newlines in
 697     a diversion.  The escape sequence `\?' is also recognized in copy
 698     mode and turned into a single internal code; it is this code that
 699     terminates ANYTHING.  Thus the following example prints 4.
 700
 701
 702          .nr x 1
 703          .nf
 704          .di d
 705          \?\\?\\\\?\\\\\\\\nx\\\\?\\?\?
 706          .di
 707          .nr x 2
 708          .di e
 709          .d
 710          .di
 711          .nr x 3
 712          .di f
 713          .e
 714          .di
 715          .nr x 4
 716          .f
 717
 718     Both escapes read the data in copy mode.
 719
 720     If `\!' is used in the top-level diversion, its argument is
 721     directly embedded into the `gtroff' intermediate output.  This can
 722     be used for example to control a postprocessor which processes the
 723     data before it is sent to the device driver.
 724
 725     The `\?' escape used in the top-level diversion produces no output
 726     at all; its argument is simply ignored.
 727
 728 -- Request: .output string
 729     Emit STRING directly to the `gtroff' intermediate output (subject
 730     to copy-mode interpretation); this is similar to `\!' used at the
 731     top level.  An initial double quote in STRING is stripped off to
 732     allow initial blanks.
 733
 734     This request can't be used before the first page has started - if
 735     you get an error, simply insert `.br' before the `output' request.
 736
 737     Without argument, `output' is ignored.
 738
 739     Use with caution!  It is normally only needed for mark-up used by a
 740     postprocessor which does something with the output before sending
 741     it to the output device, filtering out STRING again.
 742
 743 -- Request: .asciify div
 744     "Unformat" the diversion specified by DIV in such a way that ASCII
 745     characters, characters translated with the `trin' request, space
 746     characters, and some escape sequences that were formatted and
 747     diverted are treated like ordinary input characters when the
 748     diversion is reread.  It can be also used for gross hacks; for
 749     example, the following sets register `n' to 1.
 750
 751
 752          .tr @.
 753          .di x
 754          @nr n 1
 755          .br
 756          .di
 757          .tr @@
 758          .asciify x
 759          .x
 760
 761     *Note Copy-in Mode::.
 762
 763 -- Request: .unformat div
 764     Like `asciify', unformat the specified diversion.  However,
 765     `unformat' only unformats spaces and tabs between words.
 766     Unformatted tabs are treated as input tokens, and spaces are
 767     stretchable again.
 768
 769     The vertical size of lines is not preserved; glyph information
 770     (font, font size, space width, etc.) is retained.
 771
 772
 773File: groff,  Node: Environments,  Next: Suppressing output,  Prev: Diversions,  Up: gtroff Reference
 774
 7755.26 Environments
 776=================
 777
 778It happens frequently that some text should be printed in a certain
 779format regardless of what may be in effect at the time, for example, in
 780a trap invoked macro to print headers and footers.  To solve this
 781`gtroff' processes text in "environments".  An environment contains
 782most of the parameters that control text processing.  It is possible to
 783switch amongst these environments; by default `gtroff' processes text
 784in environment 0.  The following is the information kept in an
 785environment.
 786
 787   * font parameters (size, family, style, glyph height and slant, space
 788     and sentence space size)
 789
 790   * page parameters (line length, title length, vertical spacing, line
 791     spacing, indentation, line numbering, centering, right-justifying,
 792     underlining, hyphenation data)
 793
 794   * fill and adjust mode
 795
 796   * tab stops, tab and leader characters, escape character, no-break
 797     and hyphen indicators, margin character data
 798
 799   * partially collected lines
 800
 801   * input traps
 802
 803   * drawing and fill colours
 804
 805   These environments may be given arbitrary names (see *Note
 806Identifiers::, for more info).  Old versions of `troff' only had
 807environments named `0', `1', and `2'.
 808
 809 -- Request: .ev [env]
 810 -- Register: \n[.ev]
 811     Switch to another environment.  The argument ENV is the name of
 812     the environment to switch to.  With no argument, `gtroff' switches
 813     back to the previous environment.  There is no limit on the number
 814     of named environments; they are created the first time that they
 815     are referenced.  The `.ev' read-only register contains the name or
 816     number of the current environment.  This is a string-valued
 817     register.
 818
 819     Note that a call to `ev' (with argument) pushes the previously
 820     active environment onto a stack.  If, say, environments `foo',
 821     `bar', and `zap' are called (in that order), the first `ev'
 822     request without parameter switches back to environment `bar'
 823     (which is popped off the stack), and a second call switches back
 824     to environment `foo'.
 825
 826     Here is an example:
 827
 828
 829          .ev footnote-env
 830          .fam N
 831          .ps 6
 832          .vs 8
 833          .ll -.5i
 834          .ev
 835
 836          ...
 837
 838          .ev footnote-env
 839          \(dg Note the large, friendly letters.
 840          .ev
 841
 842
 843 -- Request: .evc env
 844     Copy the environment ENV into the current environment.
 845
 846     The following environment data is not copied:
 847
 848        * Partially filled lines.
 849
 850        * The status whether the previous line was interrupted.
 851
 852        * The number of lines still to center, or to right-justify, or
 853          to underline (with or without underlined spaces); they are
 854          set to zero.
 855
 856        * The status whether a temporary indentation is active.
 857
 858        * Input traps and its associated data.
 859
 860        * Line numbering mode is disabled; it can be reactivated with
 861          `.nm +0'.
 862
 863        * The number of consecutive hyphenated lines (set to zero).
 864
 865 -- Register: \n[.w]
 866 -- Register: \n[.cht]
 867 -- Register: \n[.cdp]
 868 -- Register: \n[.csk]
 869     The `\n[.w]' register contains the width of the last glyph added
 870     to the current environment.
 871
 872     The `\n[.cht]' register contains the height of the last glyph
 873     added to the current environment.
 874
 875     The `\n[.cdp]' register contains the depth of the last glyph added
 876     to the current environment.  It is positive for glyphs extending
 877     below the baseline.
 878
 879     The `\n[.csk]' register contains the "skew" (how far to the right
 880     of the glyph's center that `gtroff' should place an accent) of the
 881     last glyph added to the current environment.
 882
 883 -- Register: \n[.n]
 884     The `\n[.n]' register contains the length of the previous output
 885     line in the current environment.
 886
 887
 888File: groff,  Node: Suppressing output,  Next: Colors,  Prev: Environments,  Up: gtroff Reference
 889
 8905.27 Suppressing output
 891=======================
 892
 893 -- Escape: \Onum
 894     Disable or enable output depending on the value of NUM:
 895
 896    `\O0'
 897          Disable any glyphs from being emitted to the device driver,
 898          provided that the escape occurs at the outer level (see
 899          `\O[3]' and `\O[4]').  Motion is not suppressed so
 900          effectively `\O[0]' means _pen up_.
 901
 902    `\O1'
 903          Enable output of glyphs, provided that the escape occurs at
 904          the outer level.
 905
 906     `\O0' and `\O1' also reset the four registers `opminx', `opminy',
 907     `opmaxx', and `opmaxy' to -1.  *Note Register Index::.  These four
 908     registers mark the top left and bottom right hand corners of a box
 909     which encompasses all written glyphs.
 910
 911     For example the input text:
 912
 913
 914          Hello \O[0]world \O[1]this is a test.
 915
 916     produces the following output:
 917
 918
 919          Hello       this is a test.
 920
 921    `\O2'
 922          Provided that the escape occurs at the outer level, enable
 923          output of glyphs and also write out to `stderr' the page
 924          number and four registers encompassing the glyphs previously
 925          written since the last call to `\O'.
 926
 927    `\O3'
 928          Begin a nesting level.  At start-up, `gtroff' is at outer
 929          level.
 930
 931    `\O4'
 932          End a nesting level.
 933
 934    `\O[5PFILENAME]'
 935          This escape is `grohtml' specific.  Provided that this escape
 936          occurs at the outer nesting level write the `filename' to
 937          `stderr'.  The position of the image, P, must be specified
 938          and must be one of `l', `r', `c', or `i' (left, right,
 939          centered, inline).  FILENAME will be associated with the
 940          production of the next inline image.
 941
 942
 943File: groff,  Node: Colors,  Next: I/O,  Prev: Suppressing output,  Up: gtroff Reference
 944
 9455.28 Colors
 946===========
 947
 948 -- Request: .color [n]
 949 -- Register: \n[.color]
 950     If N is missing or non-zero, activate colors (this is the default);
 951     otherwise, turn it off.
 952
 953     The read-only number register `.color' is 1 if colors are active,
 954     0 otherwise.
 955
 956     Internally, `color' sets a global flag; it does not produce a
 957     token.  Similar to the `cp' request, you should use it at the
 958     beginning of your document to control color output.
 959
 960     Colors can be also turned off with the `-c' command line option.
 961
 962 -- Request: .defcolor ident scheme color_components
 963     Define color with name IDENT.  SCHEME can be one of  the following
 964     values: `rgb' (three components), `cmy' (three components), `cmyk'
 965     (four components), and `gray' or `grey' (one component).
 966
 967     Color components can be given either as a hexadecimal string or as
 968     positive decimal integers in the range 0-65535.  A hexadecimal
 969     string contains all color components concatenated.  It must start
 970     with either `#' or `##'; the former specifies hex values in the
 971     range 0-255 (which are internally multiplied by 257), the latter
 972     in the range 0-65535.  Examples: `#FFC0CB' (pink), `##ffff0000ffff'
 973     (magenta).  The default color name value is device-specific
 974     (usually black).  It is possible that the default color for `\m'
 975     and `\M' is not identical.
 976
 977     A new scaling indicator `f' has been introduced which multiplies
 978     its value by 65536; this makes it convenient to specify color
 979     components as fractions in the range 0 to 1 (1f equals 65536u).
 980     Example:
 981
 982
 983          .defcolor darkgreen rgb 0.1f 0.5f 0.2f
 984
 985     Note that `f' is the default scaling indicator for the `defcolor'
 986     request, thus the above statement is equivalent to
 987
 988
 989          .defcolor darkgreen rgb 0.1 0.5 0.2
 990
 991
 992 -- Request: .gcolor [color]
 993 -- Escape: \mc
 994 -- Escape: \m(co
 995 -- Escape: \m[color]
 996 -- Register: \n[.m]
 997     Set (glyph) drawing color.  The following examples show how to
 998     turn the next four words red.
 999
1000
1001          .gcolor red
1002          these are in red
1003          .gcolor
1004          and these words are in black.
1005
1006
1007          \m[red]these are in red\m[] and these words are in black.
1008
1009     The escape `\m[]' returns to the previous color, as does a call to
1010     `gcolor' without an argument.
1011
1012     The name of the current drawing color is available in the
1013     read-only, string-valued number register `.m'.
1014
1015     The drawing color is associated with the current environment
1016     (*note Environments::).
1017
1018     Note that `\m' doesn't produce an input token in `gtroff'.  As a
1019     consequence, it can be used in requests like `mc' (which expects a
1020     single character as an argument) to change the color on the fly:
1021
1022
1023          .mc \m[red]x\m[]
1024
1025
1026 -- Request: .fcolor [color]
1027 -- Escape: \Mc
1028 -- Escape: \M(co
1029 -- Escape: \M[color]
1030 -- Register: \n[.M]
1031     Set fill (background) color for filled objects drawn with the
1032     `\D'...'' commands.
1033
1034     A red ellipse can be created with the following code:
1035
1036
1037          \M[red]\h'0.5i'\D'E 2i 1i'\M[]
1038
1039     The escape `\M[]' returns to the previous fill color, as does a
1040     call to `fcolor' without an argument.
1041
1042     The name of the current fill (background) color is available in the
1043     read-only, string-valued number register `.M'.
1044
1045     The fill color is associated with the current environment (*note
1046     Environments::).
1047
1048     Note that `\M' doesn't produce an input token in `gtroff'.
1049
1050
1051File: groff,  Node: I/O,  Next: Postprocessor Access,  Prev: Colors,  Up: gtroff Reference
1052
10535.29 I/O
1054========
1055
1056`gtroff' has several requests for including files:
1057
1058 -- Request: .so file
1059     Read in the specified FILE and includes it in place of the `so'
1060     request.  This is quite useful for large documents, e.g. keeping
1061     each chapter in a separate file.  *Note gsoelim::, for more
1062     information.
1063
1064     Since `gtroff' replaces the `so' request with the contents of
1065     `file', it makes a difference whether the data is terminated with
1066     a newline or not: Assuming that file `xxx' contains the word `foo'
1067     without a final newline, this
1068
1069
1070          This is
1071          .so xxx
1072          bar
1073
1074     yields `This is foobar'.
1075
1076     The search path for FILE can be controlled with the `-I' command
1077     line option.
1078
1079 -- Request: .pso command
1080     Read the standard output from the specified COMMAND and includes
1081     it in place of the `pso' request.
1082
1083     This request causes an error if used in safer mode (which is the
1084     default).  Use `groff''s or `troff''s `-U' option to activate
1085     unsafe mode.
1086
1087     The comment regarding a final newline for the `so' request is valid
1088     for `pso' also.
1089
1090 -- Request: .mso file
1091     Identical to the `so' request except that `gtroff' searches for
1092     the specified FILE in the same directories as macro files for the
1093     the `-m' command line option.  If the file name to be included has
1094     the form `NAME.tmac' and it isn't found, `mso' tries to include
1095     `tmac.NAME' and vice versa.
1096
1097 -- Request: .trf file
1098 -- Request: .cf file
1099     Transparently output the contents of FILE.  Each line is output as
1100     if it were preceded by `\!'; however, the lines are not subject to
1101     copy mode interpretation.  If the file does not end with a newline,
1102     then a newline is added (`trf' only).  For example, to define a
1103     macro `x' containing the contents of file `f', use
1104
1105
1106          .di x
1107          .trf f
1108          .di
1109
1110     Both `trf' and `cf', when used in a diversion, embeds an object in
1111     the diversion which, when reread, causes the contents of FILE to
1112     be transparently copied through to the output.  In UNIX `troff',
1113     the contents of FILE is immediately copied through to the output
1114     regardless of whether there is a current diversion; this behaviour
1115     is so anomalous that it must be considered a bug.
1116
1117     While `cf' copies the contents of FILE completely unprocessed,
1118     `trf' disallows characters such as NUL that are not valid `gtroff'
1119     input characters (*note Identifiers::).
1120
1121     Both requests cause a line break.
1122
1123 -- Request: .nx [file]
1124     Force `gtroff' to continue processing of the file specified as an
1125     argument.  If no argument is given, immediately jump to the end of
1126     file.
1127
1128 -- Request: .rd [prompt [arg1 arg2 ...]]
1129     Read from standard input, and include what is read as though it
1130     were part of the input file.  Text is read until a blank line is
1131     encountered.
1132
1133     If standard input is a TTY input device (keyboard), write PROMPT
1134     to standard error, followed by a colon (or send BEL for a beep if
1135     no argument is given).
1136
1137     Arguments after PROMPT are available for the input.  For example,
1138     the line
1139
1140
1141          .rd data foo bar
1142
1143     with the input `This is \$2.' prints
1144
1145
1146          This is bar.
1147
1148
1149   Using the `nx' and `rd' requests, it is easy to set up form letters.
1150The form letter template is constructed like this, putting the
1151following lines into a file called `repeat.let':
1152
1153
1154     .ce
1155     \*(td
1156     .sp 2
1157     .nf
1158     .rd
1159     .sp
1160     .rd
1161     .fi
1162     Body of letter.
1163     .bp
1164     .nx repeat.let
1165
1166When this is run, a file containing the following lines should be
1167redirected in.  Note that requests included in this file are executed
1168as though they were part of the form letter.  The last block of input
1169is the `ex' request which tells `groff' to stop processing.  If this
1170was not there, `groff' would not know when to stop.
1171
1172
1173     Trent A. Fisher
1174     708 NW 19th Av., #202
1175     Portland, OR  97209
1176
1177     Dear Trent,
1178
1179     Len Adollar
1180     4315 Sierra Vista
1181     San Diego, CA  92103
1182
1183     Dear Mr. Adollar,
1184
1185     .ex
1186
1187 -- Request: .pi pipe
1188     Pipe the output of `gtroff' to the shell command(s) specified by
1189     PIPE.  This request must occur before `gtroff' has a chance to
1190     print anything.
1191
1192     `pi' causes an error if used in safer mode (which is the default).
1193     Use `groff''s or `troff''s `-U' option to activate unsafe mode.
1194
1195     Multiple calls to `pi' are allowed, acting as a chain.  For
1196     example,
1197
1198
1199          .pi foo
1200          .pi bar
1201          ...
1202
1203     is the same as `.pi foo | bar'.
1204
1205     Note that the intermediate output format of `gtroff' is piped to
1206     the specified commands.  Consequently, calling `groff' without the
1207     `-Z' option normally causes a fatal error.
1208
1209 -- Request: .sy cmds
1210 -- Register: \n[systat]
1211     Execute the shell command(s) specified by CMDS.  The output is not
1212     saved anyplace, so it is up to the user to do so.
1213
1214     This request causes an error if used in safer mode (which is the
1215     default).  Use `groff''s or `troff''s `-U' option to activate
1216     unsafe mode.
1217
1218     For example, the following code fragment introduces the current
1219     time into a document:
1220
1221
1222          .sy perl -e 'printf ".nr H %d\\n.nr M %d\\n.nr S %d\\n",\
1223                       (localtime(time))[2,1,0]' > /tmp/x\n[$$]
1224          .so /tmp/x\n[$$]
1225          .sy rm /tmp/x\n[$$]
1226          \nH:\nM:\nS
1227
1228     Note that this works by having the `perl' script (run by `sy')
1229     print out the `nr' requests which set the number registers `H',
1230     `M', and `S', and then reads those commands in with the `so'
1231     request.
1232
1233     For most practical purposes, the number registers `seconds',
1234     `minutes', and `hours' which are initialized at start-up of
1235     `gtroff' should be sufficient.  Use the `af' request to get a
1236     formatted output:
1237
1238
1239          .af hours 00
1240          .af minutes 00
1241          .af seconds 00
1242          \n[hours]:\n[minutes]:\n[seconds]
1243
1244     The `systat' read-write number register contains the return value
1245     of the `system()' function executed by the last `sy' request.
1246
1247 -- Request: .open stream file
1248 -- Request: .opena stream file
1249     Open the specified FILE for writing and associates the specified
1250     STREAM with it.
1251
1252     The `opena' request is like `open', but if the file exists, append
1253     to it instead of truncating it.
1254
1255     Both `open' and `opena' cause an error if used in safer mode
1256     (which is the default).  Use `groff''s or `troff''s `-U' option to
1257     activate unsafe mode.
1258
1259 -- Request: .write stream data
1260 -- Request: .writec stream data
1261     Write to the file associated with the specified STREAM.  The
1262     stream must previously have been the subject of an open request.
1263     The remainder of the line is interpreted as the `ds' request reads
1264     its second argument: A leading `"' is stripped, and it is read in
1265     copy-in mode.
1266
1267     The `writec' request is like `write', but only `write' appends a
1268     newline to the data.
1269
1270 -- Request: .writem stream xx
1271     Write the contents of the macro or string XX to the file
1272     associated with the specified STREAM.
1273
1274     XX is read in copy mode, i.e., already formatted elements are
1275     ignored.  Consequently, diversions must be unformatted with the
1276     `asciify' request before calling `writem'.  Usually, this means a
1277     loss of information.
1278
1279 -- Request: .close stream
1280     Close the specified STREAM; the stream is no longer an acceptable
1281     argument to the `write' request.
1282
1283     Here a simple macro to write an index entry.
1284
1285
1286          .open idx test.idx
1287          .
1288          .de IX
1289          .  write idx \\n[%] \\$*
1290          ..
1291          .
1292          .IX test entry
1293          .
1294          .close idx
1295
1296
1297 -- Escape: \Ve
1298 -- Escape: \V(ev
1299 -- Escape: \V[env]
1300     Interpolate the contents of the specified environment variable ENV
1301     (one-character name E, two-character name EV) as returned by the
1302     function `getenv'.  `\V' is interpreted in copy-in mode.
1303
1304
1305File: groff,  Node: Postprocessor Access,  Next: Miscellaneous,  Prev: I/O,  Up: gtroff Reference
1306
13075.30 Postprocessor Access
1308=========================
1309
1310There are two escapes which give information directly to the
1311postprocessor.  This is particularly useful for embedding POSTSCRIPT
1312into the final document.
1313
1314 -- Escape: \X'xxx'
1315     Embeds its argument into the `gtroff' output preceded with `x X'.
1316
1317     The escapes `\&', `\)', `\%', and `\:' are ignored within `\X',
1318     `\ ' and `\~' are converted to single space characters.  All other
1319     escapes (except `\\' which produces a backslash) cause an error.
1320
1321     If the `use_charnames_in_special' keyword is set in the `DESC'
1322     file, special characters no longer cause an error; the name XX is
1323     represented as `\(XX)' in the `x X' output command.  Additionally,
1324     the backslash is represented as `\\'.
1325
1326     `use_charnames_in_special' is currently used by `grohtml' only.
1327
1328 -- Escape: \Yn
1329 -- Escape: \Y(nm
1330 -- Escape: \Y[name]
1331     This is approximately equivalent to `\X'\*[NAME]'' (one-character
1332     name N, two-character name NM).  However, the contents of the
1333     string or macro NAME are not interpreted; also it is permitted for
1334     NAME to have been defined as a macro and thus contain newlines (it
1335     is not permitted for the argument to `\X' to contain newlines).
1336     The inclusion of newlines requires an extension to the UNIX `troff'
1337     output format, and confuses drivers that do not know about this
1338     extension (*note Device Control Commands::).
1339
1340   *Note Output Devices::.
1341
1342
1343File: groff,  Node: Miscellaneous,  Next: Gtroff Internals,  Prev: Postprocessor Access,  Up: gtroff Reference
1344
13455.31 Miscellaneous
1346==================
1347
1348This section documents parts of `gtroff' which cannot (yet) be
1349categorized elsewhere in this manual.
1350
1351 -- Request: .nm [start [inc [space [indent]]]]
1352     Print line numbers.  START is the line number of the _next_ output
1353     line.  INC indicates which line numbers are printed.  For example,
1354     the value 5 means to emit only line numbers which are multiples
1355     of 5; this defaults to 1.  SPACE is the space to be left between
1356     the number and the text; this defaults to one digit space.  The
1357     fourth argument is the indentation of the line numbers, defaulting
1358     to zero.  Both SPACE and INDENT are given as multiples of digit
1359     spaces; they can be negative also.  Without any arguments, line
1360     numbers are turned off.
1361
1362     `gtroff' reserves three digit spaces for the line number (which is
1363     printed right-justified) plus the amount given by INDENT; the
1364     output lines are concatenated to the line numbers, separated by
1365     SPACE, and _without_ reducing the line length.  Depending on the
1366     value of the horizontal page offset (as set with the `po'
1367     request), line numbers which are longer than the reserved space
1368     stick out to the left, or the whole line is moved to the right.
1369
1370     Parameters corresponding to missing arguments are not changed; any
1371     non-digit argument (to be more precise, any argument starting with
1372     a character valid as a delimiter for identifiers) is also treated
1373     as missing.
1374
1375     If line numbering has been disabled with a call to `nm' without an
1376     argument, it can be reactivated with `.nm +0', using the
1377     previously active line numbering parameters.
1378
1379     The parameters of `nm' are associated with the current environment
1380     (*note Environments::).  The current output line number is
1381     available in the number register `ln'.
1382
1383
1384          .po 1m
1385          .ll 2i
1386          This test shows how line numbering works with groff.
1387          .nm 999
1388          This test shows how line numbering works with groff.
1389          .br
1390          .nm xxx 3 2
1391          .ll -\w'0'u
1392          This test shows how line numbering works with groff.
1393          .nn 2
1394          This test shows how line numbering works with groff.
1395
1396     And here the result:
1397
1398
1399           This  test shows how
1400           line numbering works
1401           999 with   groff.   This
1402          1000 test shows how  line
1403          1001 numbering works with
1404          1002 groff.
1405                This test shows how
1406                line      numbering
1407           works  with  groff.
1408           This test shows how
1409          1005  line      numbering
1410                works with groff.
1411
1412
1413 -- Request: .nn [skip]
1414     Temporarily turn off line numbering.  The argument is the number
1415     of lines not to be numbered; this defaults to 1.
1416
1417 -- Request: .mc glyph [dist]
1418     Print a "margin character" to the right of the text.(1) (*note
1419     Miscellaneous-Footnote-1::)  The first argument is the glyph to be
1420     printed.  The second argument is the distance away from the right
1421     margin.  If missing, the previously set value is used; default is
1422     10pt).  For text lines that are too long (that is, longer than the
1423     text length plus DIST), the margin character is directly appended
1424     to the lines.
1425
1426     With no arguments the margin character is turned off.  If this
1427     occurs before a break, no margin character is printed.
1428
1429     For compatibility with AT&T `troff', a call to `mc' to set the
1430     margin character can't be undone immediately; at least one line
1431     gets a margin character.  Thus
1432
1433
1434          .ll 1i
1435          .mc \[br]
1436          .mc
1437          xxx
1438          .br
1439          xxx
1440
1441     produces
1442
1443
1444          xxx        |
1445          xxx
1446
1447     For empty lines and lines produced by the `tl' request no margin
1448     character is emitted.
1449
1450     The margin character is associated with the current environment
1451     (*note Environments::).
1452
1453     This is quite useful for indicating text that has changed, and, in
1454     fact, there are programs available for doing this (they are called
1455     `nrchbar' and `changebar' and can be found in any
1456     `comp.sources.unix' archive).
1457
1458
1459          .ll 3i
1460          .mc |
1461          This paragraph is highlighted with a margin
1462          character.
1463          .sp
1464          Note that vertical space isn't marked.
1465          .br
1466          \&
1467          .br
1468          But we can fake it with `\&'.
1469
1470     Result:
1471
1472
1473          This  paragraph is highlighted |
1474          with a margin character.       |
1475
1476          Note that vertical space isn't |
1477          marked.                        |
1478                                         |
1479          But we can fake it with `\&'.  |
1480
1481
1482 -- Request: .psbb filename
1483 -- Register: \n[llx]
1484 -- Register: \n[lly]
1485 -- Register: \n[urx]
1486 -- Register: \n[ury]
1487     Retrieve the bounding box of the PostScript image found in
1488     FILENAME.  The file must conform to Adobe's "Document Structuring
1489     Conventions" (DSC); the command searches for a `%%BoundingBox'
1490     comment and extracts the bounding box values into the number
1491     registers `llx', `lly', `urx', and `ury'.  If an error occurs (for
1492     example, `psbb' cannot find the `%%BoundingBox' comment), it sets
1493     the four number registers to zero.
1494
1495     The search path for FILENAME can be controlled with the `-I'
1496     command line option.
1497
1498
1499File: groff,  Node: Miscellaneous-Footnotes,  Up: Miscellaneous
1500
1501   (1) "Margin character" is a misnomer since it is an output glyph.
1502
1503
1504File: groff,  Node: Gtroff Internals,  Next: Debugging,  Prev: Miscellaneous,  Up: gtroff Reference
1505
15065.32 `gtroff' Internals
1507=======================
1508
1509`gtroff' processes input in three steps.  One or more input characters
1510are converted to an "input token".(1) (*note Gtroff
1511Internals-Footnote-1::)  Then, one or more input tokens are converted
1512to an "output node".  Finally, output nodes are converted to the
1513intermediate output language understood by all output devices.
1514
1515   Actually, before step one happens, `gtroff' converts certain escape
1516sequences into reserved input characters (not accessible by the user);
1517such reserved characters are used for other internal processing also -
1518this is the very reason why not all characters are valid input.  *Note
1519Identifiers::, for more on this topic.
1520
1521   For example, the input string `fi\[:u]' is converted into a
1522character token `f', a character token `i', and a special token `:u'
1523(representing u umlaut).  Later on, the character tokens `f' and `i'
1524are merged to a single output node representing the ligature glyph `fi'
1525(provided the current font has a glyph for this ligature); the same
1526happens with `:u'.  All output glyph nodes are `processed' which means
1527that they are invariably associated with a given font, font size,
1528advance width, etc.  During the formatting process, `gtroff' itself
1529adds various nodes to control the data flow.
1530
1531   Macros, diversions, and strings collect elements in two chained
1532lists: a list of input tokens which have been passed unprocessed, and a
1533list of output nodes.  Consider the following the diversion.
1534
1535
1536     .di xxx
1537     a
1538     \!b
1539     c
1540     .br
1541     .di
1542
1543It contains these elements.
1544
1545node list            token list   element number
1546line start node      --           1
1547glyph node `a'       --           2
1548word space node      --           3
1549--                   `b'          4
1550--                   `\n'         5
1551glyph node `c'       --           6
1552vertical size node   --           7
1553vertical size node   --           8
1554--                   `\n'         9
1555
1556Elements 1, 7, and 8 are inserted by `gtroff'; the latter two (which
1557are always present) specify the vertical extent of the last line,
1558possibly modified by `\x'.  The `br' request finishes the current
1559partial line, inserting a newline input token which is subsequently
1560converted to a space when the diversion is reread.  Note that the word
1561space node has a fixed width which isn't stretchable anymore.  To
1562convert horizontal space nodes back to input tokens, use the `unformat'
1563request.
1564
1565   Macros only contain elements in the token list (and the node list is
1566empty); diversions and strings can contain elements in both lists.
1567
1568   Note that the `chop' request simply reduces the number of elements
1569in a macro, string, or diversion by one.  Exceptions are "compatibility
1570save" and "compatibility ignore" input tokens which are ignored.  The
1571`substring' request also ignores those input tokens.
1572
1573   Some requests like `tr' or `cflags' work on glyph identifiers only;
1574this means that the associated glyph can be changed without destroying
1575this association.  This can be very helpful for substituting glyphs.
1576In the following example, we assume that glyph `foo' isn't available by
1577default, so we provide a substitution using the `fchar' request and map
1578it to input character `x'.
1579
1580
1581     .fchar \[foo] foo
1582     .tr x \[foo]
1583
1584Now let us assume that we install an additional special font `bar'
1585which has glyph `foo'.
1586
1587
1588     .special bar
1589     .rchar \[foo]
1590
1591Since glyphs defined with `fchar' are searched before glyphs in special
1592fonts, we must call `rchar' to remove the definition of the fallback
1593glyph.  Anyway, the translation is still active; `x' now maps to the
1594real glyph `foo'.
1595
1596   Macro and request arguments preserve the compatibility mode:
1597
1598
1599     .cp 1     \" switch to compatibility mode
1600     .de xx
1601     \\$1
1602     ..
1603     .cp 0     \" switch compatibility mode off
1604     .xx caf\['e]
1605         => café
1606
1607Since compatibility mode is on while `de' is called, the macro `xx'
1608activates compatibility mode while executing.  Argument `$1' can still
1609be handled properly because it inherits the compatibility mode status
1610which was active at the point where `xx' is called.
1611
1612   After expansion of the parameters, the compatibility save and restore
1613tokens are removed.
1614
1615
1616File: groff,  Node: Gtroff Internals-Footnotes,  Up: Gtroff Internals
1617
1618   (1) Except the escapes `\f', `\F', `\H', `\m', `\M', `\R', `\s', and
1619`\S' which are processed immediately if not in copy-in mode.
1620
1621
1622File: groff,  Node: Debugging,  Next: Implementation Differences,  Prev: Gtroff Internals,  Up: gtroff Reference
1623
16245.33 Debugging
1625==============
1626
1627`gtroff' is not easy to debug, but there are some useful features and
1628strategies for debugging.
1629
1630 -- Request: .lf line [filename]
1631     Change the line number and optionally the file name `gtroff' shall
1632     use for error and warning messages.  LINE is the input line number
1633     of the _next_ line.
1634
1635     Without argument, the request is ignored.
1636
1637     This is a debugging aid for documents which are split into many
1638     files, then put together with `soelim' and other preprocessors.
1639     Usually, it isn't invoked manually.
1640
1641     Note that other `troff' implementations (including the original
1642     AT&T version) handle `lf' differently.  For them, LINE changes the
1643     line number of the _current_ line.
1644
1645 -- Request: .tm string
1646 -- Request: .tm1 string
1647 -- Request: .tmc string
1648     Send STRING to the standard error output; this is very useful for
1649     printing debugging messages among other things.
1650
1651     STRING is read in copy mode.
1652
1653     The `tm' request ignores leading spaces of STRING; `tm1' handles
1654     its argument similar to the `ds' request: a leading double quote
1655     in STRING is stripped to allow initial blanks.
1656
1657     The `tmc' request is similar to `tm1' but does not append a
1658     newline (as is done in `tm' and `tm1').
1659
1660 -- Request: .ab [string]
1661     Similar to the `tm' request, except that it causes `gtroff' to
1662     stop processing.  With no argument it prints `User Abort.' to
1663     standard error.
1664
1665 -- Request: .ex
1666     The `ex' request also causes `gtroff' to stop processing; see also
1667     *Note I/O::.
1668
1669   When doing something involved it is useful to leave the debugging
1670statements in the code and have them turned on by a command line flag.
1671
1672
1673     .if \n(DB .tm debugging output
1674
1675To activate these statements say
1676
1677
1678     groff -rDB=1 file
1679
1680   If it is known in advance that there will be many errors and no
1681useful output, `gtroff' can be forced to suppress formatted output with
1682the `-z' flag.
1683
1684 -- Request: .pm
1685     Print the entire symbol table on `stderr'.  Names of all defined
1686     macros, strings, and diversions are print together with their size
1687     in bytes.  Since `gtroff' sometimes adds nodes by itself, the
1688     returned size can be larger than expected.
1689
1690     This request differs from UNIX `troff': `gtroff' reports the sizes
1691     of diversions, ignores an additional argument to print only the
1692     total of the sizes, and the size isn't returned in blocks of 128
1693     characters.
1694
1695 -- Request: .pnr
1696     Print the names and contents of all currently defined number
1697     registers on `stderr'.
1698
1699 -- Request: .ptr
1700     Print the names and positions of all traps (not including input
1701     line traps and diversion traps) on `stderr'.  Empty slots in the
1702     page trap list are printed as well, because they can affect the
1703     priority of subsequently planted traps.
1704
1705 -- Request: .fl
1706     Instruct `gtroff' to flush its output immediately.  The intent is
1707     for interactive use, but this behaviour is currently not
1708     implemented in `gtroff'.  Contrary to UNIX `troff', TTY output is
1709     sent to a device driver also (`grotty'), making it non-trivial to
1710     communicate interactively.
1711
1712     This request causes a line break.
1713
1714 -- Request: .backtrace
1715     Print a backtrace of the input stack to the standard error stream.
1716
1717     Consider the following in file `test':
1718
1719
1720          .de xxx
1721          .  backtrace
1722          ..
1723          .de yyy
1724          .  xxx
1725          ..
1726          .
1727          .yyy
1728
1729     On execution, `gtroff' prints the following:
1730
1731
1732          test:2: backtrace: macro `xxx'
1733          test:5: backtrace: macro `yyy'
1734          test:8: backtrace: file `test'
1735
1736     The option `-b' of `gtroff' internally calls a variant of this
1737     request on each error and warning.
1738
1739 -- Register: \n[slimit]
1740     Use the `slimit' number register to set the maximum number of
1741     objects on the input stack.  If `slimit' is less than or equal
1742     to 0, there is no limit set.  With no limit, a buggy recursive
1743     macro can exhaust virtual memory.
1744
1745     The default value is 1000; this is a compile-time constant.
1746
1747 -- Request: .warnscale si
1748     Set the scaling indicator used in warnings to SI.  Valid values for
1749     SI are `u', `i', `c', `p', and `P'.  At startup, it is set to `i'.
1750
1751 -- Request: .spreadwarn [limit]
1752     Make `gtroff' emit a warning if the additional space inserted for
1753     each space between words in an output line is larger or equal to
1754     LIMIT.  A negative value is changed to zero; no argument toggles
1755     the warning on and off without changing LIMIT.  The default scaling
1756     indicator is `m'.  At startup, `spreadwarn' is deactivated, and
1757     LIMIT is set to 3m.
1758
1759     For example,
1760
1761
1762          .spreadwarn 0.2m
1763
1764     will cause a warning if `gtroff' must add 0.2m or more for each
1765     interword space in a line.
1766
1767     This request is active only if text is justified to both margins
1768     (using `.ad b').
1769
1770   `gtroff' has command line options for printing out more warnings
1771(`-w') and for printing backtraces (`-b') when a warning or an error
1772occurs.  The most verbose level of warnings is `-ww'.
1773
1774 -- Request: .warn [flags]
1775 -- Register: \n[.warn]
1776     Control the level of warnings checked for.  The FLAGS are the sum
1777     of the numbers associated with each warning that is to be enabled;
1778     all other warnings are disabled.  The number associated with each
1779     warning is listed below.  For example, `.warn 0' disables all
1780     warnings, and `.warn 1' disables all warnings except that about
1781     missing glyphs.  If no argument is given, all warnings are enabled.
1782
1783     The read-only number register `.warn' contains the current warning
1784     level.
1785
1786* Menu:
1787
1788* Warnings::
1789
1790
1791File: groff,  Node: Warnings,  Prev: Debugging,  Up: Debugging
1792
17935.33.1 Warnings
1794---------------
1795
1796The warnings that can be given to `gtroff' are divided into the
1797following categories.  The name associated with each warning is used by
1798the `-w' and `-W' options; the number is used by the `warn' request and
1799by the `.warn' register.
1800
1801`char'
1802`1'
1803     Non-existent glyphs.(1) (*note Warnings-Footnote-1::)  This is
1804     enabled by default.
1805
1806`number'
1807`2'
1808     Invalid numeric expressions.  This is enabled by default.  *Note
1809     Expressions::.
1810
1811`break'
1812`4'
1813     In fill mode, lines which could not be broken so that their length
1814     was less than the line length.  This is enabled by default.
1815
1816`delim'
1817`8'
1818     Missing or mismatched closing delimiters.
1819
1820`el'
1821`16'
1822     Use of the `el' request with no matching `ie' request.  *Note
1823     if-else::.
1824
1825`scale'
1826`32'
1827     Meaningless scaling indicators.
1828
1829`range'
1830`64'
1831     Out of range arguments.
1832
1833`syntax'
1834`128'
1835     Dubious syntax in numeric expressions.
1836
1837`di'
1838`256'
1839     Use of `di' or `da' without an argument when there is no current
1840     diversion.
1841
1842`mac'
1843`512'
1844     Use of undefined strings, macros and diversions.  When an undefined
1845     string, macro, or diversion is used, that string is automatically
1846     defined as empty.  So, in most cases, at most one warning is given
1847     for each name.
1848
1849`reg'
1850`1024'
1851     Use of undefined number registers.  When an undefined number
1852     register is used, that register is automatically defined to have a
1853     value of 0.  So, in most cases, at most one warning is given for
1854     use of a particular name.
1855
1856`tab'
1857`2048'
1858     Use of a tab character where a number was expected.
1859
1860`right-brace'
1861`4096'
1862     Use of `\}' where a number was expected.
1863
1864`missing'
1865`8192'
1866     Requests that are missing non-optional arguments.
1867
1868`input'
1869`16384'
1870     Invalid input characters.
1871
1872`escape'
1873`32768'
1874     Unrecognized escape sequences.  When an unrecognized escape
1875     sequence `\X' is encountered, the escape character is ignored, and
1876     X is printed.
1877
1878`space'
1879`65536'
1880     Missing space between a request or macro and its argument.  This
1881     warning is given when an undefined name longer than two characters
1882     is encountered, and the first two characters of the name make a
1883     defined name.  The request or macro is not invoked.  When this
1884     warning is given, no macro is automatically defined.  This is
1885     enabled by default.  This warning never occurs in compatibility
1886     mode.
1887
1888`font'
1889`131072'
1890     Non-existent fonts.  This is enabled by default.
1891
1892`ig'
1893`262144'
1894     Invalid escapes in text ignored with the `ig' request.  These are
1895     conditions that are errors when they do not occur in ignored text.
1896
1897`color'
1898`524288'
1899     Color related warnings.
1900
1901`all'
1902     All warnings except `di', `mac' and `reg'.  It is intended that
1903     this covers all warnings that are useful with traditional macro
1904     packages.
1905
1906`w'
1907     All warnings.
1908
1909
1910File: groff,  Node: Warnings-Footnotes,  Up: Warnings
1911
1912   (1) `char' is a misnomer since it reports missing glyphs - there
1913aren't missing input characters, only invalid ones.
1914
1915
1916File: groff,  Node: Implementation Differences,  Prev: Debugging,  Up: gtroff Reference
1917
19185.34 Implementation Differences
1919===============================
1920
1921GNU `troff' has a number of features which cause incompatibilities with
1922documents written with old versions of `troff'.
1923
1924   Long names cause some incompatibilities.  UNIX `troff' interprets
1925
1926
1927     .dsabcd
1928
1929as defining a string `ab' with contents `cd'.  Normally, GNU `troff'
1930interprets this as a call of a macro named `dsabcd'.  Also UNIX `troff'
1931interprets `\*[' or `\n[' as references to a string or number register
1932called `['.  In GNU `troff', however, this is normally interpreted as
1933the start of a long name.  In compatibility mode GNU `troff' interprets
1934long names in the traditional way (which means that they are not
1935recognized as names).
1936
1937 -- Request: .cp [n]
1938 -- Request: .do cmd
1939 -- Register: \n[.C]
1940     If N is missing or non-zero, turn on compatibility mode;
1941     otherwise, turn it off.
1942
1943     The read-only number register `.C' is 1 if compatibility mode is
1944     on, 0 otherwise.
1945
1946     Compatibility mode can be also turned on with the `-C' command line
1947     option.
1948
1949     The `do' request turns off compatibility mode while executing its
1950     arguments as a `gtroff' command.
1951
1952
1953          .do fam T
1954
1955     executes the `fam' request when compatibility mode is enabled.
1956
1957     `gtroff' restores the previous compatibility setting before
1958     interpreting any files sourced by the CMD.
1959
1960   Two other features are controlled by `-C'.  If not in compatibility
1961mode, GNU `troff' preserves the input level in delimited arguments:
1962
1963
1964     .ds xx '
1965     \w'abc\*(xxdef'
1966
1967In compatibility mode, the string `72def'' is returned; without `-C'
1968the resulting string is `168' (assuming a TTY output device).
1969
1970   Finally, the escapes `\f', `\H', `\m', `\M', `\R', `\s', and `\S'
1971are transparent for recognizing the beginning of a line only in
1972compatibility mode (this is a rather obscure feature).  For example,
1973the code
1974
1975
1976     .de xx
1977     Hallo!
1978     ..
1979     \fB.xx\fP
1980
1981prints `Hallo!' in bold face if in compatibility mode, and `.xx' in
1982bold face otherwise.
1983
1984   GNU `troff' does not allow the use of the escape sequences `\|',
1985`\^', `\&', `\{', `\}', `\<SP>', `\'', `\`', `\-', `\_', `\!', `\%',
1986and `\c' in names of strings, macros, diversions, number registers,
1987fonts or environments; UNIX `troff' does.  The `\A' escape sequence
1988(*note Identifiers::) may be helpful in avoiding use of these escape
1989sequences in names.
1990
1991   Fractional point sizes cause one noteworthy incompatibility.  In
1992UNIX `troff' the `ps' request ignores scale indicators and thus
1993
1994
1995     .ps 10u
1996
1997sets the point size to 10 points, whereas in GNU `troff' it sets the
1998point size to 10 scaled points.  *Note Fractional Type Sizes::, for
1999more information.
2000
2001   In GNU `troff' there is a fundamental difference between
2002(unformatted) input characters and (formatted) output glyphs.
2003Everything that affects how a glyph is output is stored with the glyph
2004node; once a glyph node has been constructed it is unaffected by any
2005subsequent requests that are executed, including `bd', `cs', `tkf',
2006`tr', or `fp' requests.  Normally glyphs are constructed from input
2007characters at the moment immediately before the glyph is added to the
2008current output line.  Macros, diversions and strings are all, in fact,
2009the same type of object; they contain lists of input characters and
2010glyph nodes in any combination.  A glyph node does not behave like an
2011input character for the purposes of macro processing; it does not
2012inherit any of the special properties that the input character from
2013which it was constructed might have had.  For example,
2014
2015
2016     .di x
2017     \\\\
2018     .br
2019     .di
2020     .x
2021
2022prints `\\' in GNU `troff'; each pair of input backslashes is turned
2023into one output backslash and the resulting output backslashes are not
2024interpreted as escape characters when they are reread.  UNIX `troff'
2025would interpret them as escape characters when they were reread and
2026would end up printing one `\'.  The correct way to obtain a printable
2027backslash is to use the `\e' escape sequence: This always prints a
2028single instance of the current escape character, regardless of whether
2029or not it is used in a diversion; it also works in both GNU `troff' and
2030UNIX `troff'.(1) (*note Implementation Differences-Footnote-1::)  To
2031store, for some reason, an escape sequence in a diversion that will be
2032interpreted when the diversion is reread, either use the traditional
2033`\!' transparent output facility, or, if this is unsuitable, the new
2034`\?' escape sequence.
2035
2036   *Note Diversions::, and *Note Gtroff Internals::, for more
2037information.
2038
2039
2040File: groff,  Node: Implementation Differences-Footnotes,  Up: Implementation Differences
2041
2042   (1) To be completely independent of the current escape character,
2043use `\(rs' which represents a reverse solidus (backslash) glyph.
2044
2045
2046File: groff,  Node: Preprocessors,  Next: Output Devices,  Prev: gtroff Reference,  Up: Top
2047
20486 Preprocessors
2049***************
2050
2051This chapter describes all preprocessors that come with `groff' or
2052which are freely available.
2053
2054* Menu:
2055
2056* geqn::
2057* gtbl::
2058* gpic::
2059* ggrn::
2060* grap::
2061* grefer::
2062* gsoelim::
2063
2064
2065File: groff,  Node: geqn,  Next: gtbl,  Prev: Preprocessors,  Up: Preprocessors
2066
20676.1 `geqn'
2068==========
2069
2070* Menu:
2071
2072* Invoking geqn::
2073
2074
2075File: groff,  Node: Invoking geqn,  Prev: geqn,  Up: geqn
2076
20776.1.1 Invoking `geqn'
2078---------------------
2079
2080
2081File: groff,  Node: gtbl,  Next: gpic,  Prev: geqn,  Up: Preprocessors
2082
20836.2 `gtbl'
2084==========
2085
2086* Menu:
2087
2088* Invoking gtbl::
2089
2090
2091File: groff,  Node: Invoking gtbl,  Prev: gtbl,  Up: gtbl
2092
20936.2.1 Invoking `gtbl'
2094---------------------
2095
2096
2097File: groff,  Node: gpic,  Next: ggrn,  Prev: gtbl,  Up: Preprocessors
2098
20996.3 `gpic'
2100==========
2101
2102* Menu:
2103
2104* Invoking gpic::
2105
2106
2107File: groff,  Node: Invoking gpic,  Prev: gpic,  Up: gpic
2108
21096.3.1 Invoking `gpic'
2110---------------------
2111
2112
2113File: groff,  Node: ggrn,  Next: grap,  Prev: gpic,  Up: Preprocessors
2114
21156.4 `ggrn'
2116==========
2117
2118* Menu:
2119
2120* Invoking ggrn::
2121
2122
2123File: groff,  Node: Invoking ggrn,  Prev: ggrn,  Up: ggrn
2124
21256.4.1 Invoking `ggrn'
2126---------------------
2127
2128
2129File: groff,  Node: grap,  Next: grefer,  Prev: ggrn,  Up: Preprocessors
2130
21316.5 `grap'
2132==========
2133
2134A free implementation of `grap', written by Ted Faber, is available as
2135an extra package from the following address:
2136
2137     `http://www.lunabase.org/~faber/Vault/software/grap/'
2138
2139
2140File: groff,  Node: grefer,  Next: gsoelim,  Prev: grap,  Up: Preprocessors
2141
21426.6 `grefer'
2143============
2144
2145* Menu:
2146
2147* Invoking grefer::
2148
2149
2150File: groff,  Node: Invoking grefer,  Prev: grefer,  Up: grefer
2151
21526.6.1 Invoking `grefer'
2153-----------------------
2154
2155
2156File: groff,  Node: gsoelim,  Prev: grefer,  Up: Preprocessors
2157
21586.7 `gsoelim'
2159=============
2160
2161* Menu:
2162
2163* Invoking gsoelim::
2164
2165
2166File: groff,  Node: Invoking gsoelim,  Prev: gsoelim,  Up: gsoelim
2167
21686.7.1 Invoking `gsoelim'
2169------------------------
2170
2171
2172File: groff,  Node: Output Devices,  Next: File formats,  Prev: Preprocessors,  Up: Top
2173
21747 Output Devices
2175****************
2176
2177* Menu:
2178
2179* Special Characters::
2180* grotty::
2181* grops::
2182* grodvi::
2183* grolj4::
2184* grolbp::
2185* grohtml::
2186* gxditview::
2187
2188
2189File: groff,  Node: Special Characters,  Next: grotty,  Prev: Output Devices,  Up: Output Devices
2190
21917.1 Special Characters
2192======================
2193
2194*Note Font Files::.
2195
2196
2197File: groff,  Node: grotty,  Next: grops,  Prev: Special Characters,  Up: Output Devices
2198
21997.2 `grotty'
2200============
2201
2202* Menu:
2203
2204* Invoking grotty::
2205
2206
2207File: groff,  Node: Invoking grotty,  Prev: grotty,  Up: grotty
2208
22097.2.1 Invoking `grotty'
2210-----------------------
2211
2212
2213File: groff,  Node: grops,  Next: grodvi,  Prev: grotty,  Up: Output Devices
2214
22157.3 `grops'
2216===========
2217
2218* Menu:
2219
2220* Invoking grops::
2221* Embedding PostScript::
2222
2223
2224File: groff,  Node: Invoking grops,  Next: Embedding PostScript,  Prev: grops,  Up: grops
2225
22267.3.1 Invoking `grops'
2227----------------------
2228
2229
2230File: groff,  Node: Embedding PostScript,  Prev: Invoking grops,  Up: grops
2231
22327.3.2 Embedding POSTSCRIPT
2233--------------------------
2234
2235
2236File: groff,  Node: grodvi,  Next: grolj4,  Prev: grops,  Up: Output Devices
2237
22387.4 `grodvi'
2239============
2240
2241* Menu:
2242
2243* Invoking grodvi::
2244
2245
2246File: groff,  Node: Invoking grodvi,  Prev: grodvi,  Up: grodvi
2247
22487.4.1 Invoking `grodvi'
2249-----------------------
2250
2251
2252File: groff,  Node: grolj4,  Next: grolbp,  Prev: grodvi,  Up: Output Devices
2253
22547.5 `grolj4'
2255============
2256
2257* Menu:
2258
2259* Invoking grolj4::
2260
2261
2262File: groff,  Node: Invoking grolj4,  Prev: grolj4,  Up: grolj4
2263
22647.5.1 Invoking `grolj4'
2265-----------------------
2266
2267
2268File: groff,  Node: grolbp,  Next: grohtml,  Prev: grolj4,  Up: Output Devices
2269
22707.6 `grolbp'
2271============
2272
2273* Menu:
2274
2275* Invoking grolbp::
2276
2277
2278File: groff,  Node: Invoking grolbp,  Prev: grolbp,  Up: grolbp
2279
22807.6.1 Invoking `grolbp'
2281-----------------------
2282
2283
2284File: groff,  Node: grohtml,  Next: gxditview,  Prev: grolbp,  Up: Output Devices
2285
22867.7 `grohtml'
2287=============
2288
2289* Menu:
2290
2291* Invoking grohtml::
2292* grohtml specific registers and strings::
2293
2294
2295File: groff,  Node: Invoking grohtml,  Next: grohtml specific registers and strings,  Prev: grohtml,  Up: grohtml
2296
22977.7.1 Invoking `grohtml'
2298------------------------
2299
2300
2301File: groff,  Node: grohtml specific registers and strings,  Prev: Invoking grohtml,  Up: grohtml
2302
23037.7.2 `grohtml' specific registers and strings
2304----------------------------------------------
2305
2306 -- Register: \n[ps4html]
2307 -- String: \*[www-image-template]
2308     The registers `ps4html' and `www-image-template' are defined by
2309     the `pre-grohtml' preprocessor.  `pre-grohtml' reads in the
2310     `troff' input, marks up the inline equations and passes the result
2311     firstly to
2312
2313
2314          troff -Tps -rps4html=1 -dwww-image-template=TEMPLATE
2315
2316     and secondly to
2317
2318
2319          troff -Thtml
2320
2321     The PostScript device is used to create all the image files, and
2322     the register `ps4html' enables the macro sets to ignore floating
2323     keeps, footers, and headings.
2324
2325     The register `www-image-template' is set to the user specified
2326     template name or the default name.
2327
2328
2329File: groff,  Node: gxditview,  Prev: grohtml,  Up: Output Devices
2330
23317.8 `gxditview'
2332===============
2333
2334* Menu:
2335
2336* Invoking gxditview::
2337
2338
2339File: groff,  Node: Invoking gxditview,  Prev: gxditview,  Up: gxditview
2340
23417.8.1 Invoking `gxditview'
2342--------------------------
2343
2344
2345File: groff,  Node: File formats,  Next: Installation,  Prev: Output Devices,  Up: Top
2346
23478 File formats
2348**************
2349
2350All files read and written by `gtroff' are text files.  The following
2351two sections describe their format.
2352
2353* Menu:
2354
2355* gtroff Output::
2356* Font Files::
2357
2358
2359File: groff,  Node: gtroff Output,  Next: Font Files,  Prev: File formats,  Up: File formats
2360
23618.1 `gtroff' Output
2362===================
2363
2364This section describes the intermediate output format of GNU `troff'.
2365This output is produced by a run of `gtroff' before it is fed into a
2366device postprocessor program.
2367
2368   As `groff' is a wrapper program around `gtroff' that automatically
2369calls a postprocessor, this output does not show up normally.  This is
2370why it is called "intermediate".  `groff' provides the option `-Z' to
2371inhibit postprocessing, such that the produced intermediate output is
2372sent to standard output just like calling `gtroff' manually.
2373
2374   Here, the term "troff output" describes what is output by `gtroff',
2375while "intermediate output" refers to the language that is accepted by
2376the parser that prepares this output for the postprocessors.  This
2377parser is smarter on whitespace and implements obsolete elements for
2378compatibility, otherwise both formats are the same.(1) (*note gtroff
2379Output-Footnote-1::)
2380
2381   The main purpose of the intermediate output concept is to facilitate
2382the development of postprocessors by providing a common programming
2383interface for all devices.  It has a language of its own that is
2384completely different from the `gtroff' language.  While the `gtroff'
2385language is a high-level programming language for text processing, the
2386intermediate output language is a kind of low-level assembler language
2387by specifying all positions on the page for writing and drawing.
2388
2389   The intermediate output produced by `gtroff' is fairly readable,
2390while output from AT&T `troff' is rather hard to understand because of
2391strange habits that are still supported, but not used any longer by
2392`gtroff'.
2393
2394* Menu:
2395
2396* Language Concepts::
2397* Command Reference::
2398* Intermediate Output Examples::
2399* Output Language Compatibility::
2400
2401
2402File: groff,  Node: gtroff Output-Footnotes,  Up: gtroff Output
2403
2404   (1) The parser and postprocessor for intermediate output can be
2405found in the file
2406`GROFF-SOURCE-DIR/src/libs/libdriver/input.cpp'.
2407
2408
2409File: groff,  Node: Language Concepts,  Next: Command Reference,  Prev: gtroff Output,  Up: gtroff Output
2410
24118.1.1 Language Concepts
2412-----------------------
2413
2414During the run of `gtroff', the input data is cracked down to the
2415information on what has to be printed at what position on the intended
2416device.  So the language of the intermediate output format can be quite
2417small.  Its only elements are commands with and without arguments.  In
2418this section, the term "command" always refers to the intermediate
2419output language, and never to the `gtroff' language used for document
2420formatting.  There are commands for positioning and text writing, for
2421drawing, and for device controlling.
2422
2423* Menu:
2424
2425* Separation::
2426* Argument Units::
2427* Document Parts::
2428
2429
2430File: groff,  Node: Separation,  Next: Argument Units,  Prev: Language Concepts,  Up: Language Concepts
2431
24328.1.1.1 Separation
2433..................
2434
2435AT&T `troff' output has strange requirements on whitespace.  The
2436`gtroff' output parser, however, is smart about whitespace by making it
2437maximally optional.  The whitespace characters, i.e., the tab, space,
2438and newline characters, always have a syntactical meaning.  They are
2439never printable because spacing within the output is always done by
2440positioning commands.
2441
2442   Any sequence of space or tab characters is treated as a single
2443"syntactical space".  It separates commands and arguments, but is only
2444required when there would occur a clashing between the command code and
2445the arguments without the space.  Most often, this happens when
2446variable-length command names, arguments, argument lists, or command
2447clusters meet.  Commands and arguments with a known, fixed length need
2448not be separated by syntactical space.
2449
2450   A line break is a syntactical element, too.  Every command argument
2451can be followed by whitespace, a comment, or a newline character.  Thus
2452a "syntactical line break" is defined to consist of optional
2453syntactical space that is optionally followed by a comment, and a
2454newline character.
2455
2456   The normal commands, those for positioning and text, consist of a
2457single letter taking a fixed number of arguments.  For historical
2458reasons, the parser allows to stack such commands on the same line, but
2459fortunately, in `gtroff''s intermediate output, every command with at
2460least one argument is followed by a line break, thus providing
2461excellent readability.
2462
2463   The other commands - those for drawing and device controlling - have
2464a more complicated structure; some recognize long command names, and
2465some take a variable number of arguments.  So all `D' and `x' commands
2466were designed to request a syntactical line break after their last
2467argument.  Only one command, `x X', has an argument that can stretch
2468over several lines; all other commands must have all of their arguments
2469on the same line as the command, i.e., the arguments may not be
2470splitted by a line break.
2471
2472   Empty lines (these are lines containing only space and/or a
2473comment), can occur everywhere.  They are just ignored.
2474
2475
2476File: groff,  Node: Argument Units,  Next: Document Parts,  Prev: Separation,  Up: Language Concepts
2477
24788.1.1.2 Argument Units
2479......................
2480
2481Some commands take integer arguments that are assumed to represent
2482values in a measurement unit, but the letter for the corresponding
2483scale indicator is not written with the output command arguments.  Most
2484commands assume the scale indicator `u', the basic unit of the device,
2485some use `z', the scaled point unit of the device, while others, such
2486as the color commands, expect plain integers.
2487
2488   Note that single characters can have the eighth bit set, as can the
2489names of fonts and special characters.  The names of characters and
2490fonts can be of arbitrary length.  A character that is to be printed
2491will always be in the current font.
2492
2493   A string argument is always terminated by the next whitespace
2494character (space, tab, or newline); an embedded `#' character is
2495regarded as part of the argument, not as the beginning of a comment
2496command.  An integer argument is already terminated by the next
2497non-digit character, which then is regarded as the first character of
2498the next argument or command.
2499
2500
2501File: groff,  Node: Document Parts,  Prev: Argument Units,  Up: Language Concepts
2502
25038.1.1.3 Document Parts
2504......................
2505
2506A correct intermediate output document consists of two parts, the
2507"prologue" and the "body".
2508
2509   The task of the prologue is to set the general device parameters
2510using three exactly specified commands.  `gtroff''s prologue is
2511guaranteed to consist of the following three lines (in that order):
2512
2513
2514     x T DEVICE
2515     x res N H V
2516     x init
2517
2518with the arguments set as outlined in *Note Device Control Commands::.
2519Note that the parser for the intermediate output format is able to
2520swallow additional whitespace and comments as well even in the prologue.
2521
2522   The body is the main section for processing the document data.
2523Syntactically, it is a sequence of any commands different from the ones
2524used in the prologue.  Processing is terminated as soon as the first
2525`x stop' command is encountered; the last line of any `gtroff'
2526intermediate output always contains such a command.
2527
2528   Semantically, the body is page oriented.  A new page is started by a
2529`p' command.  Positioning, writing, and drawing commands are always
2530done within the current page, so they cannot occur before the first `p'
2531command.  Absolute positioning (by the `H' and `V' commands) is done
2532relative to the current page; all other positioning is done relative to
2533the current location within this page.
2534
2535
2536File: groff,  Node: Command Reference,  Next: Intermediate Output Examples,  Prev: Language Concepts,  Up: gtroff Output
2537
25388.1.2 Command Reference
2539-----------------------
2540
2541This section describes all intermediate output commands, both from AT&T
2542`troff' as well as the `gtroff' extensions.
2543
2544* Menu:
2545
2546* Comment Command::
2547* Simple Commands::
2548* Graphics Commands::
2549* Device Control Commands::
2550* Obsolete Command::
2551
2552
2553File: groff,  Node: Comment Command,  Next: Simple Commands,  Prev: Command Reference,  Up: Command Reference
2554
25558.1.2.1 Comment Command
2556.......................
2557
2558`#ANYTHING<end of line>'
2559     A comment.  Ignore any characters from the `#' character up to the
2560     next newline character.
2561
2562     This command is the only possibility for commenting in the
2563     intermediate output.  Each comment can be preceded by arbitrary
2564     syntactical space; every command can be terminated by a comment.
2565
2566
2567File: groff,  Node: Simple Commands,  Next: Graphics Commands,  Prev: Comment Command,  Up: Command Reference
2568
25698.1.2.2 Simple Commands
2570.......................
2571
2572The commands in this subsection have a command code consisting of a
2573single character, taking a fixed number of arguments.  Most of them are
2574commands for positioning and text writing.  These commands are smart
2575about whitespace.  Optionally, syntactical space can be inserted
2576before, after, and between the command letter and its arguments.  All
2577of these commands are stackable, i.e., they can be preceded by other
2578simple commands or followed by arbitrary other commands on the same
2579line.  A separating syntactical space is only necessary when two
2580integer arguments would clash or if the preceding argument ends with a
2581string argument.
2582
2583`C XXX<whitespace>'
2584     Print a special character named XXX.  The trailing syntactical
2585     space or line break is necessary to allow glyph names of arbitrary
2586     length.  The glyph is printed at the current print position; the
2587     glyph's size is read from the font file.  The print position is
2588     not changed.
2589
2590`c G'
2591     Print glyph G at the current print position;(1) (*note Simple
2592     Commands-Footnote-1::) the glyph's size is read from the font
2593     file.  The print position is not changed.
2594
2595`f N'
2596     Set font to font number N (a non-negative integer).
2597
2598`H N'
2599     Move right to the absolute vertical position N (a non-negative
2600     integer in basic units `u' relative to left edge of current page.
2601
2602`h N'
2603     Move N (a non-negative integer) basic units `u' horizontally to
2604     the right.  The original UNIX troff manual allows negative values
2605     for N also, but `gtroff' doesn't use this.
2606
2607`m COLOR-SCHEME [COMPONENT ...]'
2608     Set the color for text (glyphs), line drawing, and the outline of
2609     graphic objects using different color schemes; the analoguous
2610     command for the filling color of graphic objects is `DF'.  The
2611     color components are specified as integer arguments between 0 and
2612     65536.  The number of color components and their meaning vary for
2613     the different color schemes.  These commands are generated by
2614     `gtroff''s escape sequence `\m'.  No position changing.  These
2615     commands are a `gtroff' extension.
2616
2617    `mc CYAN MAGENTA YELLOW'
2618          Set color using the CMY color scheme, having the 3 color
2619          components CYAN, MAGENTA, and YELLOW.
2620
2621    `md'
2622          Set color to the default color value (black in most cases).
2623          No component arguments.
2624
2625    `mg GRAY'
2626          Set color to the shade of gray given by the argument, an
2627          integer between 0 (black) and 65536 (white).
2628
2629    `mk CYAN MAGENTA YELLOW BLACK'
2630          Set color using the CMYK color scheme, having the 4 color
2631          components CYAN, MAGENTA, YELLOW, and BLACK.
2632
2633    `mr RED GREEN BLUE'
2634          Set color using the RGB color scheme, having the 3 color
2635          components RED, GREEN, and BLUE.
2636
2637`N N'
2638     Print glyph with index N (a non-negative integer) of the current
2639     font.  This command is a `gtroff' extension.
2640
2641`n B A'
2642     Inform the device about a line break, but no positioning is done by
2643     this command.  In AT&T `troff', the integer arguments B and A
2644     informed about the space before and after the current line to make
2645     the intermediate output more human readable without performing any
2646     action.  In `groff', they are just ignored, but they must be
2647     provided for compatibility reasons.
2648
2649`p N'
2650     Begin a new page in the outprint.  The page number is set to N.
2651     This page is completely independent of pages formerly processed
2652     even if those have the same page number.  The vertical position on
2653     the outprint is automatically set to 0.  All positioning, writing,
2654     and drawing is always done relative to a page, so a `p' command
2655     must be issued before any of these commands.
2656
2657`s N'
2658     Set point size to N scaled points (this is unit `z').  AT&T
2659     `troff' used the unit points (`p') instead.  *Note Output Language
2660     Compatibility::.
2661
2662`t XXX<whitespace>'
2663`t XXX DUMMY-ARG<whitespace>'
2664     Print a word, i.e., a sequence of characters XXX representing
2665     output glyphs which names are single characters, terminated by a
2666     space character or a line break; an optional second integer
2667     argument is ignored (this allows the formatter to generate an even
2668     number of arguments).  The first glyph should be printed at the
2669     current position, the current horizontal position should then be
2670     increased by the width of the first glyph, and so on for each
2671     glyph.  The widths of the glyphs are read from the font file,
2672     scaled for the current point size, and rounded to a multiple of
2673     the horizontal resolution.  Special characters cannot be printed
2674     using this command (use the `C' command for special characters).
2675     This command is a `gtroff' extension; it is only used for devices
2676     whose `DESC' file contains the `tcommand' keyword (*note DESC File
2677     Format::).
2678
2679`u N XXX<whitespace>'
2680     Print word with track kerning.  This is the same as the `t'
2681     command except that after printing each glyph, the current
2682     horizontal position is increased by the sum of the width of that
2683     glyph and N (an integer in basic units `u').  This command is a
2684     `gtroff' extension; it is only used for devices whose `DESC' file
2685     contains the `tcommand' keyword (*note DESC File Format::).
2686
2687`V N'
2688     Move down to the absolute vertical position N (a non-negative
2689     integer in basic units `u') relative to upper edge of current page.
2690
2691`v N'
2692     Move N basic units `u' down (N is a non-negative integer).  The
2693     original UNIX troff manual allows negative values for N also, but
2694     `gtroff' doesn't use this.
2695
2696`w'
2697     Informs about a paddable white space to increase readability.  The
2698     spacing itself must be performed explicitly by a move command.
2699
2700
2701File: groff,  Node: Simple Commands-Footnotes,  Up: Simple Commands
2702
2703   (1) `c' is actually a misnomer since it outputs a glyph.
2704
2705
2706File: groff,  Node: Graphics Commands,  Next: Device Control Commands,  Prev: Simple Commands,  Up: Command Reference
2707
27088.1.2.3 Graphics Commands
2709.........................
2710
2711Each graphics or drawing command in the intermediate output starts with
2712the letter `D', followed by one or two characters that specify a
2713subcommand; this is followed by a fixed or variable number of integer
2714arguments that are separated by a single space character.  A `D'
2715command may not be followed by another command on the same line (apart
2716from a comment), so each `D' command is terminated by a syntactical
2717line break.
2718
2719   `gtroff' output follows the classical spacing rules (no space
2720between command and subcommand, all arguments are preceded by a single
2721space character), but the parser allows optional space between the
2722command letters and makes the space before the first argument optional.
2723As usual, each space can be any sequence of tab and space characters.
2724
2725   Some graphics commands can take a variable number of arguments.  In
2726this case, they are integers representing a size measured in basic
2727units `u'.  The arguments called H1, H2, ..., HN stand for horizontal
2728distances where positive means right, negative left.  The arguments
2729called V1, V2, ..., VN stand for vertical distances where positive
2730means down, negative up.  All these distances are offsets relative to
2731the current location.
2732
2733   Each graphics command directly corresponds to a similar `gtroff'
2734`\D' escape sequence.  *Note Drawing Requests::.
2735
2736   Unknown `D' commands are assumed to be device-specific.  Its
2737arguments are parsed as strings; the whole information is then sent to
2738the postprocessor.
2739
2740   In the following command reference, the syntax element <line
2741break> means a syntactical line break as defined above.
2742
2743`D~ H1 V1 H2 V2 ... HN VN<line break>'
2744     Draw B-spline from current position to offset (H1,V1), then to
2745     offset (H2,V2), if given, etc. up to (HN,VN).  This command takes
2746     a variable number of argument pairs; the current position is moved
2747     to the terminal point of the drawn curve.
2748
2749`Da H1 V1 H2 V2<line break>'
2750     Draw arc from current position to (H1,V1)+(H2,V2) with center at
2751     (H1,V1); then move the current position to the final point of the
2752     arc.
2753
2754`DC D<line break>'
2755`DC D DUMMY-ARG<line break>'
2756     Draw a solid circle using the current fill color with diameter D
2757     (integer in basic units `u') with leftmost point at the current
2758     position; then move the current position to the rightmost point of
2759     the circle.  An optional second integer argument is ignored (this
2760     allows the formatter to generate an even number of arguments).
2761     This command is a `gtroff' extension.
2762
2763`Dc D<line break>'
2764     Draw circle line with diameter D (integer in basic units `u') with
2765     leftmost point at the current position; then move the current
2766     position to the rightmost point of the circle.
2767
2768`DE H V<line break>'
2769     Draw a solid ellipse in the current fill color with a horizontal
2770     diameter of H and a vertical diameter of V (both integers in basic
2771     units `u') with the leftmost point at the current position; then
2772     move to the rightmost point of the ellipse.  This command is a
2773     `gtroff' extension.
2774
2775`De H V<line break>'
2776     Draw an outlined ellipse with a horizontal diameter of H and a
2777     vertical diameter of V (both integers in basic units `u') with the
2778     leftmost point at current position; then move to the rightmost
2779     point of the ellipse.
2780
2781`DF COLOR-SCHEME [COMPONENT ...]<line break>'
2782     Set fill color for solid drawing objects using different color
2783     schemes; the analoguous command for setting the color of text, line
2784     graphics, and the outline of graphic objects is `m'.  The color
2785     components are specified as integer arguments between 0 and 65536.
2786     The number of color components and their meaning vary for the
2787     different color schemes.  These commands are generated by
2788     `gtroff''s escape sequences `\D'F ...'' and `\M' (with no other
2789     corresponding graphics commands).  No position changing.  This
2790     command is a `gtroff' extension.
2791
2792    `DFc CYAN MAGENTA YELLOW<line break>'
2793          Set fill color for solid drawing objects using the CMY color
2794          scheme, having the 3 color components CYAN, MAGENTA, and
2795          YELLOW.
2796
2797    `DFd<line break>'
2798          Set fill color for solid drawing objects to the default fill
2799          color value (black in most cases).  No component arguments.
2800
2801    `DFg GRAY<line break>'
2802          Set fill color for solid drawing objects to the shade of gray
2803          given by the argument, an integer between 0 (black) and 65536
2804          (white).
2805
2806    `DFk CYAN MAGENTA YELLOW BLACK<line break>'
2807          Set fill color for solid drawing objects using the CMYK color
2808          scheme, having the 4 color components CYAN, MAGENTA, YELLOW,
2809          and BLACK.
2810
2811    `DFr RED GREEN BLUE<line break>'
2812          Set fill color for solid drawing objects using the RGB color
2813          scheme, having the 3 color components RED, GREEN, and BLUE.
2814
2815`Df N<line break>'
2816     The argument N must be an integer in the range -32767 to 32767.
2817
2818    0 <= N <= 1000
2819          Set the color for filling solid drawing objects to a shade of
2820          gray, where 0 corresponds to solid white, 1000 (the default)
2821          to solid black, and values in between to intermediate shades
2822          of gray; this is obsoleted by command `DFg'.
2823
2824    N < 0 or N > 1000
2825          Set the filling color to the color that is currently being
2826          used for the text and the outline, see command `m'.  For
2827          example, the command sequence
2828
2829
2830               mg 0 0 65536
2831               Df -1
2832
2833          sets all colors to blue.
2834
2835     No position changing.  This command is a `gtroff' extension.
2836
2837`Dl H V<line break>'
2838     Draw line from current position to offset (H,V) (integers in basic
2839     units `u'); then set current position to the end of the drawn line.
2840
2841`Dp H1 V1 H2 V2 ... HN VN<line break>'
2842     Draw a polygon line from current position to offset (H1,V1), from
2843     there to offset (H2,V2), etc. up to offset (HN,VN), and from there
2844     back to the starting position.  For historical reasons, the
2845     position is changed by adding the sum of all arguments with odd
2846     index to the actual horizontal position and the even ones to the
2847     vertical position.  Although this doesn't make sense it is kept
2848     for compatibility.  This command is a `gtroff' extension.
2849
2850`Dp H1 V1 H2 V2 ... HN VN<line break>'
2851     Draw a solid polygon in the current fill color rather than an
2852     outlined polygon, using the same arguments and positioning as the
2853     corresponding `Dp' command.  This command is a `gtroff' extension.
2854
2855`Dt N<line break>'
2856     Set the current line thickness to N (an integer in basic units
2857     `u') if N>0; if N=0 select the smallest available line thickness;
2858     if N<0 set the line thickness proportional to the point size (this
2859     is the default before the first `Dt' command was specified).  For
2860     historical reasons, the horizontal position is changed by adding
2861     the argument to the actual horizontal position, while the vertical
2862     position is not changed.  Although this doesn't make sense it is
2863     kept for compatibility.  This command is a `gtroff' extension.
2864
2865
2866File: groff,  Node: Device Control Commands,  Next: Obsolete Command,  Prev: Graphics Commands,  Up: Command Reference
2867
28688.1.2.4 Device Control Commands
2869...............................
2870
2871Each device control command starts with the letter `x', followed by a
2872space character (optional or arbitrary space or tab in `gtroff') and a
2873subcommand letter or word; each argument (if any) must be preceded by a
2874syntactical space.  All `x' commands are terminated by a syntactical
2875line break; no device control command can be followed by another
2876command on the same line (except a comment).
2877
2878   The subcommand is basically a single letter, but to increase
2879readability, it can be written as a word, i.e., an arbitrary sequence
2880of characters terminated by the next tab, space, or newline character.
2881All characters of the subcommand word but the first are simply ignored.
2882For example, `gtroff' outputs the initialization command `x i' as
2883`x init' and the resolution command `x r' as `x res'.
2884
2885   In the following, the syntax element <line break> means a
2886syntactical line break (*note Separation::).
2887
2888`xF NAME<line break>'
2889     The `F' stands for FILENAME.
2890
2891     Use NAME as the intended name for the current file in error
2892     reports.  This is useful for remembering the original file name
2893     when `gtroff' uses an internal piping mechanism.  The input file is
2894     not changed by this command.  This command is a `gtroff' extension.
2895
2896`xf N S<line break>'
2897     The `f' stands for FONT.
2898
2899     Mount font position N (a non-negative integer) with font named S
2900     (a text word).  *Note Font Positions::.
2901
2902`xH N<line break>'
2903     The `H' stands for HEIGHT.
2904
2905     Set glyph height to N (a positive integer in scaled points `z').
2906     AT&T `troff' uses the unit points (`p') instead.  *Note Output
2907     Language Compatibility::.
2908
2909`xi<line break>'
2910     The `i' stands for INIT.
2911
2912     Initialize device.  This is the third command of the prologue.
2913
2914`xp<line break>'
2915     The `p' stands for PAUSE.
2916
2917     Parsed but ignored.  The original UNIX troff manual writes
2918
2919          pause device, can be restarted
2920
2921`xr N H V<line break>'
2922     The `r' stands for RESOLUTION.
2923
2924     Resolution is N, while H is the minimal horizontal motion, and V
2925     the minimal vertical motion possible with this device; all
2926     arguments are positive integers in basic units `u' per inch.  This
2927     is the second command of the prologue.
2928
2929`xS N<line break>'
2930     The `S' stands for SLANT.
2931
2932     Set slant to N (an integer in basic units `u').
2933
2934`xs<line break>'
2935     The `s' stands for STOP.
2936
2937     Terminates the processing of the current file; issued as the last
2938     command of any intermediate troff output.
2939
2940`xt<line break>'
2941     The `t' stands for TRAILER.
2942
2943     Generate trailer information, if any.  In GTROFF, this is actually
2944     just ignored.
2945
2946`xT XXX<line break>'
2947     The `T' stands for TYPESETTER.
2948
2949     Set name of device to word XXX, a sequence of characters ended by
2950     the next white space character.  The possible device names coincide
2951     with those from the `groff' `-T' option.  This is the first
2952     command of the prologue.
2953
2954`xu N<line break>'
2955     The `u' stands for UNDERLINE.
2956
2957     Configure underlining of spaces.  If N is 1, start underlining of
2958     spaces; if N is 0, stop underlining of spaces.  This is needed for
2959     the `cu' request in nroff mode and is ignored otherwise.  This
2960     command is a `gtroff' extension.
2961
2962`xX ANYTHING<line break>'
2963     The `x' stands for X-ESCAPE.
2964
2965     Send string ANYTHING uninterpreted to the device.  If the line
2966     following this command starts with a `+' character this line is
2967     interpreted as a continuation line in the following sense.  The
2968     `+' is ignored, but a newline character is sent instead to the
2969     device, the rest of the line is sent uninterpreted.  The same
2970     applies to all following lines until the first character of a line
2971     is not a `+' character.  This command is generated by the `gtroff'
2972     escape sequence `\X'.  The line-continuing feature is a `gtroff'
2973     extension.
2974
2975
2976File: groff,  Node: Obsolete Command,  Prev: Device Control Commands,  Up: Command Reference
2977
29788.1.2.5 Obsolete Command
2979........................
2980
2981In AT&T `troff' output, the writing of a single glyph is mostly done by
2982a very strange command that combines a horizontal move and a single
2983character giving the glyph name.  It doesn't have a command code, but
2984is represented by a 3-character argument consisting of exactly 2 digits
2985and a character.
2986
2987DDG
2988     Move right DD (exactly two decimal digits) basic units `u', then
2989     print glyph G (represented as a single character).
2990
2991     In `gtroff', arbitrary syntactical space around and within this
2992     command is allowed to be added.  Only when a preceding command on
2993     the same line ends with an argument of variable length a
2994     separating space is obligatory.  In AT&T `troff', large clusters
2995     of these and other commands are used, mostly without spaces; this
2996     made such output almost unreadable.
2997
2998   For modern high-resolution devices, this command does not make sense
2999because the width of the glyphs can become much larger than two decimal
3000digits.  In `gtroff', this is only used for the devices `X75',
3001`X75-12', `X100', and `X100-12'.  For other devices, the commands `t'
3002and `u' provide a better functionality.
3003
3004
3005File: groff,  Node: Intermediate Output Examples,  Next: Output Language Compatibility,  Prev: Command Reference,  Up: gtroff Output
3006
30078.1.3 Intermediate Output Examples
3008----------------------------------
3009
3010This section presents the intermediate output generated from the same
3011input for three different devices.  The input is the sentence `hell
3012world' fed into `gtroff' on the command line.
3013
3014High-resolution device `ps'
3015     This is the standard output of `gtroff' if no `-T' option is given.
3016
3017          shell> echo "hell world" | groff -Z -T ps
3018
3019          x T ps
3020          x res 72000 1 1
3021          x init
3022          p1
3023          x font 5 TR
3024          f5
3025          s10000
3026          V12000
3027          H72000
3028          thell
3029          wh2500
3030          tw
3031          H96620
3032          torld
3033          n12000 0
3034          x trailer
3035          V792000
3036          x stop
3037
3038     This output can be fed into `grops' to get its representation as a
3039     PostScript file.
3040
3041Low-resolution device `latin1'
3042     This is similar to the high-resolution device except that the
3043     positioning is done at a minor scale.  Some comments (lines
3044     starting with `#') were added for clarification; they were not
3045     generated by the formatter.
3046
3047          shell> echo "hell world" | groff -Z -T latin1
3048
3049          # prologue
3050          x T latin1
3051          x res 240 24 40
3052          x init
3053          # begin a new page
3054          p1
3055          # font setup
3056          x font 1 R
3057          f1
3058          s10
3059          # initial positioning on the page
3060          V40
3061          H0
3062          # write text `hell'
3063          thell
3064          # inform about space, and issue a horizontal jump
3065          wh24
3066          # write text `world'
3067          tworld
3068          # announce line break, but do nothing because ...
3069          n40 0
3070          # ... the end of the document has been reached
3071          x trailer
3072          V2640
3073          x stop
3074
3075     This output can be fed into `grotty' to get a formatted text
3076     document.
3077
3078AT&T `troff' output
3079     Since a computer monitor has a very low resolution compared to
3080     modern printers the intermediate output for the X Window devices
3081     can use the jump-and-write command with its 2-digit displacements.
3082
3083          shell> echo "hell world" | groff -Z -T X100
3084
3085          x T X100
3086          x res 100 1 1
3087          x init
3088          p1
3089          x font 5 TR
3090          f5
3091          s10
3092          V16
3093          H100
3094          # write text with jump-and-write commands
3095          ch07e07l03lw06w11o07r05l03dh7
3096          n16 0
3097          x trailer
3098          V1100
3099          x stop
3100
3101     This output can be fed into `xditview' or `gxditview' for
3102     displaying in X.
3103
3104     Due to the obsolete jump-and-write command, the text clusters in
3105     the AT&T `troff' output are almost unreadable.
3106
3107
3108File: groff,  Node: Output Language Compatibility,  Prev: Intermediate Output Examples,  Up: gtroff Output
3109
31108.1.4 Output Language Compatibility
3111-----------------------------------
3112
3113The intermediate output language of AT&T `troff' was first documented
3114in the UNIX troff manual, with later additions documented in `A
3115Typesetter-indenpendent TROFF', written by Brian Kernighan.
3116
3117   The `gtroff' intermediate output format is compatible with this
3118specification except for the following features.
3119
3120   * The classical quasi device independence is not yet implemented.
3121
3122   * The old hardware was very different from what we use today.  So the
3123     `groff' devices are also fundamentally different from the ones in
3124     AT&T `troff'.  For example, the AT&T PostScript device is called
3125     `post' and has a resolution of only 720 units per inch, suitable
3126     for printers 20 years ago, while `groff''s `ps' device has a
3127     resolution of 72000 units per inch.  Maybe, by implementing some
3128     rescaling mechanism similar to the classical quasi device
3129     independence, `groff' could emulate AT&T's `post' device.
3130
3131   * The B-spline command `D~' is correctly handled by the intermediate
3132     output parser, but the drawing routines aren't implemented in some
3133     of the postprocessor programs.
3134
3135   * The argument of the commands `s' and `x H' has the implicit unit
3136     scaled point `z' in `gtroff', while AT&T `troff' has point (`p').
3137     This isn't an incompatibility but a compatible extension, for both
3138     units coincide for all devices without a `sizescale' parameter in
3139     the `DESC' file, including all postprocessors from AT&T and
3140     `groff''s text devices.  The few `groff' devices with a
3141     `sizescale' parameter either do not exist for AT&T `troff', have a
3142     different name, or seem to have a different resolution.  So
3143     conflicts are very unlikely.
3144
3145   * The position changing after the commands `Dp', `DP', and `Dt' is
3146     illogical, but as old versions of `gtroff' used this feature it is
3147     kept for compatibility reasons.
3148
3149
3150
3151File: groff,  Node: Font Files,  Prev: gtroff Output,  Up: File formats
3152
31538.2 Font Files
3154==============
3155
3156The `gtroff' font format is roughly a superset of the `ditroff' font
3157format (as used in later versions of AT&T `troff' and its descendants).
3158Unlike the `ditroff' font format, there is no associated binary
3159format; all files are text files.(1) (*note Font Files-Footnote-1::)
3160The font files for device NAME are stored in a directory `devNAME'.
3161There are two types of file: a device description file called `DESC'
3162and for each font F a font file called `F'.
3163
3164* Menu:
3165
3166* DESC File Format::
3167* Font File Format::
3168
3169
3170File: groff,  Node: Font Files-Footnotes,  Up: Font Files
3171
3172   (1) Plan 9 `troff' has also abandoned the binary format.
3173
3174
3175File: groff,  Node: DESC File Format,  Next: Font File Format,  Prev: Font Files,  Up: Font Files
3176
31778.2.1 `DESC' File Format
3178------------------------
3179
3180The `DESC' file can contain the following types of line.  Except for
3181the `charset' keyword which must comes last (if at all), the order of
3182the lines is not important.
3183
3184`res N'
3185     There are N machine units per inch.
3186
3187`hor N'
3188     The horizontal resolution is N machine units.  All horizontal
3189     quantities are rounded to be multiples of this value.
3190
3191`vert N'
3192     The vertical resolution is N machine units.  All vertical
3193     quantities are rounded to be multiples of this value.
3194
3195`sizescale N'
3196     The scale factor for point sizes.  By default this has a value
3197     of 1.  One scaled point is equal to one point/N.  The arguments to
3198     the `unitwidth' and `sizes' commands are given in scaled points.
3199     *Note Fractional Type Sizes::, for more information.
3200
3201`unitwidth N'
3202     Quantities in the font files are given in machine units for fonts
3203     whose point size is N scaled points.
3204
3205`prepro PROGRAM'
3206     Call PROGRAM as a preprocessor.  Currently, this keyword is used
3207     by `groff' with option `-Thtml' only.
3208
3209`postpro PROGRAM'
3210     Call PROGRAM as a postprocessor.  For example, the line
3211
3212
3213          postpro grodvi
3214
3215     in the file `devdvi/DESC' makes `groff' call `grodvi' if option
3216     `-Tdvi' is given (and `-Z' isn't used).
3217
3218`tcommand'
3219     This means that the postprocessor can handle the `t' and `u'
3220     intermediate output commands.
3221
3222`sizes S1 S2 ... SN 0'
3223     This means that the device has fonts at S1, S2, ...  SN scaled
3224     points.  The list of sizes must be terminated by 0 (this is digit
3225     zero).  Each SI can also be a range of sizes M-N.  The list can
3226     extend over more than one line.
3227
3228`styles S1 S2 ... SM'
3229     The first M font positions are associated with styles S1 ... SM.
3230
3231`fonts N F1 F2 F3 ... FN'
3232     Fonts F1 ... FN are mounted in the font positions M+1, ..., M+N
3233     where M is the number of styles.  This command may extend over
3234     more than one line.  A font name of 0 means no font is mounted on
3235     the corresponding font position.
3236
3237`family FAM'
3238     The default font family is FAM.
3239
3240`use_charnames_in_special'
3241     This command indicates that `gtroff' should encode special
3242     characters inside special commands.  Currently, this is only used
3243     by the HTML output device.  *Note Postprocessor Access::.
3244
3245`papersize STRING ...'
3246     Select a paper size.  Valid values for STRING are the ISO paper
3247     types `A0'-`A7', `B0'-`B7', `C0'-`C7', `D0'-`D7', `DL', and the US
3248     paper types `letter', `legal', `tabloid', `ledger', `statement',
3249     `executive', `com10', and `monarch'.  Case is not significant for
3250     STRING if it holds predefined paper types.  Alternatively, STRING
3251     can be a file name (e.g. `/etc/papersize'); if the file can be
3252     opened, `groff' reads the first line and tests for the above paper
3253     sizes.  Finally, STRING can be a custom paper size in the format
3254     `LENGTH,WIDTH' (no spaces before and after the comma).  Both
3255     LENGTH and WIDTH must have a unit appended; valid values are `i'
3256     for inches, `C' for centimeters, `p' for points, and `P' for
3257     picas.  Example: `12c,235p'.  An argument which starts with a
3258     digit is always treated as a custom paper format.  `papersize'
3259     sets both the vertical and horizontal dimension of the output
3260     medium.
3261
3262     More than one argument can be specified; `groff' scans from left to
3263     right and uses the first valid paper specification.
3264
3265`pass_filenames'
3266     Tell `gtroff' to emit the name of the source file currently being
3267     processed.  This is achieved by the intermediate output command
3268     `F'.  Currently, this is only used by the HTML output device.
3269
3270`print PROGRAM'
3271     Use PROGRAM as a spooler program for printing.  If omitted, the
3272     `-l' and `-L' options of `groff' are ignored.
3273
3274`charset'
3275     This line and everything following in the file are ignored.  It is
3276     allowed for the sake of backwards compatibility.
3277
3278   The `res', `unitwidth', `fonts', and `sizes' lines are mandatory.
3279Other commands are ignored by `gtroff' but may be used by
3280postprocessors to store arbitrary information about the device in the
3281`DESC' file.
3282
3283   Here a list of obsolete keywords which are recognized by `groff' but
3284completely ignored: `spare1', `spare2', `biggestfont'.
3285
3286
3287File: groff,  Node: Font File Format,  Prev: DESC File Format,  Up: Font Files
3288
32898.2.2 Font File Format
3290----------------------
3291
3292A "font file", also (and probably better) called a "font description
3293file", has two sections.  The first section is a sequence of lines each
3294containing a sequence of blank delimited words; the first word in the
3295line is a key, and subsequent words give a value for that key.
3296
3297`name F'
3298     The name of the font is F.
3299
3300`spacewidth N'
3301     The normal width of a space is N.
3302
3303`slant N'
3304     The glyphs of the font have a slant of N degrees.  (Positive means
3305     forward.)
3306
3307`ligatures LIG1 LIG2 ... LIGN [0]'
3308     Glyphs LIG1, LIG2, ..., LIGN are ligatures; possible ligatures are
3309     `ff', `fi', `fl', `ffi' and `ffl'.  For backwards compatibility,
3310     the list of ligatures may be terminated with a 0.  The list of
3311     ligatures may not extend over more than one line.
3312
3313`special'
3314     The font is "special"; this means that when a glyph is requested
3315     that is not present in the current font, it is searched for in any
3316     special fonts that are mounted.
3317
3318   Other commands are ignored by `gtroff' but may be used by
3319postprocessors to store arbitrary information about the font in the font
3320file.
3321
3322   The first section can contain comments which start with the `#'
3323character and extend to the end of a line.
3324
3325   The second section contains one or two subsections.  It must contain
3326a `charset' subsection and it may also contain a `kernpairs'
3327subsection.  These subsections can appear in any order.  Each
3328subsection starts with a word on a line by itself.
3329
3330   The word `charset' starts the character set subsection.(1) (*note
3331Font File Format-Footnote-1::)  The `charset' line is followed by a
3332sequence of lines.  Each line gives information for one glyph.  A line
3333comprises a number of fields separated by blanks or tabs.  The format is
3334
3335     NAME METRICS TYPE CODE [ENTITY-NAME] [`--' COMMENT]
3336
3337NAME identifies the glyph name(2) (*note Font File Format-Footnote-2::):
3338If NAME is a single character C then it corresponds to the `gtroff'
3339input character C; if it is of the form `\C' where C is a single
3340character, then it corresponds to the special character `\[C]';
3341otherwise it corresponds to the special character `\[NAME]'.  If it is
3342exactly two characters XX it can be entered as `\(XX'.  Note that
3343single-letter special characters can't be accessed as `\C'; the only
3344exception is `\-' which is identical to `\[-]'.
3345
3346   `gtroff' supports 8-bit input characters; however some utilities
3347have difficulties with eight-bit characters.  For this reason, there is
3348a convention that the entity name `charN' is equivalent to the single
3349input character whose code is N.  For example, `char163' would be
3350equivalent to the character with code 163 which is the pounds sterling
3351sign in the ISO Latin-1 character set.  You shouldn't use `charN'
3352entities in font description files since they are related to input, not
3353output.  Otherwise, you get hard-coded connections between input and
3354output encoding which prevents use of different (input) character sets.
3355
3356   The name `---' is special and indicates that the glyph is unnamed;
3357such glyphs can only be used by means of the `\N' escape sequence in
3358`gtroff'.
3359
3360   The TYPE field gives the glyph type:
3361
3362`1'
3363     the glyph has a descender, for example, `p';
3364
3365`2'
3366     the glyph has an ascender, for example, `b';
3367
3368`3'
3369     the glyph has both an ascender and a descender, for example, `('.
3370
3371   The CODE field gives the code which the postprocessor uses to print
3372the glyph.  The glyph can also be input to `gtroff' using this code by
3373means of the `\N' escape sequence.  CODE can be any integer.  If it
3374starts with `0' it is interpreted as octal; if it starts with `0x' or
3375`0X' it is interpreted as hexadecimal.  Note, however, that the `\N'
3376escape sequence only accepts a decimal integer.
3377
3378   The ENTITY-NAME field gives an ASCII string identifying the glyph
3379which the postprocessor uses to print the `gtroff' glyph NAME.  This
3380field is optional and has been introduced so that the HTML device
3381driver can encode its character set.  For example, the glyph `\[Po]' is
3382represented as `&pound;' in HTML 4.0.
3383
3384   Anything on the line after the ENTITY-NAME field resp. after `--'
3385will be ignored.
3386
3387   The METRICS field has the form:
3388
3389     WIDTH[`,'HEIGHT[`,'DEPTH[`,'ITALIC-CORRECTION
3390       [`,'LEFT-ITALIC-CORRECTION[`,'SUBSCRIPT-CORRECTION]]]]]
3391
3392There must not be any spaces between these subfields (it has been split
3393here into two lines for better legibility only).  Missing subfields are
3394assumed to be 0.  The subfields are all decimal integers.  Since there
3395is no associated binary format, these values are not required to fit
3396into a variable of type `char' as they are in `ditroff'.  The WIDTH
3397subfield gives the width of the glyph.  The HEIGHT subfield gives the
3398height of the glyph (upwards is positive); if a glyph does not extend
3399above the baseline, it should be given a zero height, rather than a
3400negative height.  The DEPTH subfield gives the depth of the glyph, that
3401is, the distance from the baseline to the lowest point below the
3402baseline to which the glyph extends (downwards is positive); if a glyph
3403does not extend below the baseline, it should be given a zero depth,
3404rather than a negative depth.  The ITALIC-CORRECTION subfield gives the
3405amount of space that should be added after the glyph when it is
3406immediately to be followed by a glyph from a roman font.  The
3407LEFT-ITALIC-CORRECTION subfield gives the amount of space that should
3408be added before the glyph when it is immediately to be preceded by a
3409glyph from a roman font.  The SUBSCRIPT-CORRECTION gives the amount of
3410space that should be added after a glyph before adding a subscript.
3411This should be less than the italic correction.
3412
3413   A line in the `charset' section can also have the format
3414
3415
3416     NAME "
3417
3418This indicates that NAME is just another name for the glyph mentioned
3419in the preceding line.
3420
3421   The word `kernpairs' starts the kernpairs section.  This contains a
3422sequence of lines of the form:
3423
3424
3425     C1 C2 N
3426
3427This means that when glyph C1 appears next to glyph C2 the space
3428between them should be increased by N.  Most entries in the kernpairs
3429section have a negative value for N.
3430
3431
3432File: groff,  Node: Font File Format-Footnotes,  Up: Font File Format
3433
3434   (1) This keyword is misnamed since it starts a list of ordered
3435glyphs, not characters.
3436
3437   (2) The distinction between input, characters, and output, glyphs,
3438is not clearly separated in the terminology of `groff'; for example,
3439the `char' request should be called `glyph' since it defines an output
3440entity.
3441
3442
3443File: groff,  Node: Installation,  Next: Copying This Manual,  Prev: File formats,  Up: Top
3444
34459 Installation
3446**************
3447
3448
3449File: groff,  Node: Copying This Manual,  Next: Request Index,  Prev: Installation,  Up: Top
3450
3451Appendix A Copying This Manual
3452******************************
3453
3454* Menu:
3455
3456* GNU Free Documentation License::  License for copying this manual.
3457
3458
3459File: groff,  Node: GNU Free Documentation License,  Up: Copying This Manual
3460
3461A.1 GNU Free Documentation License
3462==================================
3463
3464                      Version 1.2, November 2002
3465
3466     Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.
3467     51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
3468
3469     Everyone is permitted to copy and distribute verbatim copies
3470     of this license document, but changing it is not allowed.
3471
3472  0. PREAMBLE
3473
3474     The purpose of this License is to make a manual, textbook, or other
3475     functional and useful document "free" in the sense of freedom: to
3476     assure everyone the effective freedom to copy and redistribute it,
3477     with or without modifying it, either commercially or
3478     noncommercially.  Secondarily, this License preserves for the
3479     author and publisher a way to get credit for their work, while not
3480     being considered responsible for modifications made by others.
3481
3482     This License is a kind of "copyleft", which means that derivative
3483     works of the document must themselves be free in the same sense.
3484     It complements the GNU General Public License, which is a copyleft
3485     license designed for free software.
3486
3487     We have designed this License in order to use it for manuals for
3488     free software, because free software needs free documentation: a
3489     free program should come with manuals providing the same freedoms
3490     that the software does.  But this License is not limited to
3491     software manuals; it can be used for any textual work, regardless
3492     of subject matter or whether it is published as a printed book.
3493     We recommend this License principally for works whose purpose is
3494     instruction or reference.
3495
3496  1. APPLICABILITY AND DEFINITIONS
3497
3498     This License applies to any manual or other work, in any medium,
3499     that contains a notice placed by the copyright holder saying it
3500     can be distributed under the terms of this License.  Such a notice
3501     grants a world-wide, royalty-free license, unlimited in duration,
3502     to use that work under the conditions stated herein.  The
3503     "Document", below, refers to any such manual or work.  Any member
3504     of the public is a licensee, and is addressed as "you".  You
3505     accept the license if you copy, modify or distribute the work in a
3506     way requiring permission under copyright law.
3507
3508     A "Modified Version" of the Document means any work containing the
3509     Document or a portion of it, either copied verbatim, or with
3510     modifications and/or translated into another language.
3511
3512     A "Secondary Section" is a named appendix or a front-matter section
3513     of the Document that deals exclusively with the relationship of the
3514     publishers or authors of the Document to the Document's overall
3515     subject (or to related matters) and contains nothing that could
3516     fall directly within that overall subject.  (Thus, if the Document
3517     is in part a textbook of mathematics, a Secondary Section may not
3518     explain any mathematics.)  The relationship could be a matter of
3519     historical connection with the subject or with related matters, or
3520     of legal, commercial, philosophical, ethical or political position
3521     regarding them.
3522
3523     The "Invariant Sections" are certain Secondary Sections whose
3524     titles are designated, as being those of Invariant Sections, in
3525     the notice that says that the Document is released under this
3526     License.  If a section does not fit the above definition of
3527     Secondary then it is not allowed to be designated as Invariant.
3528     The Document may contain zero Invariant Sections.  If the Document
3529     does not identify any Invariant Sections then there are none.
3530
3531     The "Cover Texts" are certain short passages of text that are
3532     listed, as Front-Cover Texts or Back-Cover Texts, in the notice
3533     that says that the Document is released under this License.  A
3534     Front-Cover Text may be at most 5 words, and a Back-Cover Text may
3535     be at most 25 words.
3536
3537     A "Transparent" copy of the Document means a machine-readable copy,
3538     represented in a format whose specification is available to the
3539     general public, that is suitable for revising the document
3540     straightforwardly with generic text editors or (for images
3541     composed of pixels) generic paint programs or (for drawings) some
3542     widely available drawing editor, and that is suitable for input to
3543     text formatters or for automatic translation to a variety of
3544     formats suitable for input to text formatters.  A copy made in an
3545     otherwise Transparent file format whose markup, or absence of
3546     markup, has been arranged to thwart or discourage subsequent
3547     modification by readers is not Transparent.  An image format is
3548     not Transparent if used for any substantial amount of text.  A
3549     copy that is not "Transparent" is called "Opaque".
3550
3551     Examples of suitable formats for Transparent copies include plain
3552     ASCII without markup, Texinfo input format, LaTeX input format,
3553     SGML or XML using a publicly available DTD, and
3554     standard-conforming simple HTML, PostScript or PDF designed for
3555     human modification.  Examples of transparent image formats include
3556     PNG, XCF and JPG.  Opaque formats include proprietary formats that
3557     can be read and edited only by proprietary word processors, SGML or
3558     XML for which the DTD and/or processing tools are not generally
3559     available, and the machine-generated HTML, PostScript or PDF
3560     produced by some word processors for output purposes only.
3561
3562     The "Title Page" means, for a printed book, the title page itself,
3563     plus such following pages as are needed to hold, legibly, the
3564     material this License requires to appear in the title page.  For
3565     works in formats which do not have any title page as such, "Title
3566     Page" means the text near the most prominent appearance of the
3567     work's title, preceding the beginning of the body of the text.
3568
3569     A section "Entitled XYZ" means a named subunit of the Document
3570     whose title either is precisely XYZ or contains XYZ in parentheses
3571     following text that translates XYZ in another language.  (Here XYZ
3572     stands for a specific section name mentioned below, such as
3573     "Acknowledgements", "Dedications", "Endorsements", or "History".)
3574     To "Preserve the Title" of such a section when you modify the
3575     Document means that it remains a section "Entitled XYZ" according
3576     to this definition.
3577
3578     The Document may include Warranty Disclaimers next to the notice
3579     which states that this License applies to the Document.  These
3580     Warranty Disclaimers are considered to be included by reference in
3581     this License, but only as regards disclaiming warranties: any other
3582     implication that these Warranty Disclaimers may have is void and
3583     has no effect on the meaning of this License.
3584
3585  2. VERBATIM COPYING
3586
3587     You may copy and distribute the Document in any medium, either
3588     commercially or noncommercially, provided that this License, the
3589     copyright notices, and the license notice saying this License
3590     applies to the Document are reproduced in all copies, and that you
3591     add no other conditions whatsoever to those of this License.  You
3592     may not use technical measures to obstruct or control the reading
3593     or further copying of the copies you make or distribute.  However,
3594     you may accept compensation in exchange for copies.  If you
3595     distribute a large enough number of copies you must also follow
3596     the conditions in section 3.
3597
3598     You may also lend copies, under the same conditions stated above,
3599     and you may publicly display copies.
3600
3601  3. COPYING IN QUANTITY
3602
3603     If you publish printed copies (or copies in media that commonly
3604     have printed covers) of the Document, numbering more than 100, and
3605     the Document's license notice requires Cover Texts, you must
3606     enclose the copies in covers that carry, clearly and legibly, all
3607     these Cover Texts: Front-Cover Texts on the front cover, and
3608     Back-Cover Texts on the back cover.  Both covers must also clearly
3609     and legibly identify you as the publisher of these copies.  The
3610     front cover must present the full title with all words of the
3611     title equally prominent and visible.  You may add other material
3612     on the covers in addition.  Copying with changes limited to the
3613     covers, as long as they preserve the title of the Document and
3614     satisfy these conditions, can be treated as verbatim copying in
3615     other respects.
3616
3617     If the required texts for either cover are too voluminous to fit
3618     legibly, you should put the first ones listed (as many as fit
3619     reasonably) on the actual cover, and continue the rest onto
3620     adjacent pages.
3621
3622     If you publish or distribute Opaque copies of the Document
3623     numbering more than 100, you must either include a
3624     machine-readable Transparent copy along with each Opaque copy, or
3625     state in or with each Opaque copy a computer-network location from
3626     which the general network-using public has access to download
3627     using public-standard network protocols a complete Transparent
3628     copy of the Document, free of added material.  If you use the
3629     latter option, you must take reasonably prudent steps, when you
3630     begin distribution of Opaque copies in quantity, to ensure that
3631     this Transparent copy will remain thus accessible at the stated
3632     location until at least one year after the last time you
3633     distribute an Opaque copy (directly or through your agents or
3634     retailers) of that edition to the public.
3635
3636     It is requested, but not required, that you contact the authors of
3637     the Document well before redistributing any large number of
3638     copies, to give them a chance to provide you with an updated
3639     version of the Document.
3640
3641  4. MODIFICATIONS
3642
3643     You may copy and distribute a Modified Version of the Document
3644     under the conditions of sections 2 and 3 above, provided that you
3645     release the Modified Version under precisely this License, with
3646     the Modified Version filling the role of the Document, thus
3647     licensing distribution and modification of the Modified Version to
3648     whoever possesses a copy of it.  In addition, you must do these
3649     things in the Modified Version:
3650
3651       A. Use in the Title Page (and on the covers, if any) a title
3652          distinct from that of the Document, and from those of
3653          previous versions (which should, if there were any, be listed
3654          in the History section of the Document).  You may use the
3655          same title as a previous version if the original publisher of
3656          that version gives permission.
3657
3658       B. List on the Title Page, as authors, one or more persons or
3659          entities responsible for authorship of the modifications in
3660          the Modified Version, together with at least five of the
3661          principal authors of the Document (all of its principal
3662          authors, if it has fewer than five), unless they release you
3663          from this requirement.
3664
3665       C. State on the Title page the name of the publisher of the
3666          Modified Version, as the publisher.
3667
3668       D. Preserve all the copyright notices of the Document.
3669
3670       E. Add an appropriate copyright notice for your modifications
3671          adjacent to the other copyright notices.
3672
3673       F. Include, immediately after the copyright notices, a license
3674          notice giving the public permission to use the Modified
3675          Version under the terms of this License, in the form shown in
3676          the Addendum below.
3677
3678       G. Preserve in that license notice the full lists of Invariant
3679          Sections and required Cover Texts given in the Document's
3680          license notice.
3681
3682       H. Include an unaltered copy of this License.
3683
3684       I. Preserve the section Entitled "History", Preserve its Title,
3685          and add to it an item stating at least the title, year, new
3686          authors, and publisher of the Modified Version as given on
3687          the Title Page.  If there is no section Entitled "History" in
3688          the Document, create one stating the title, year, authors,
3689          and publisher of the Document as given on its Title Page,
3690          then add an item describing the Modified Version as stated in
3691          the previous sentence.
3692
3693       J. Preserve the network location, if any, given in the Document
3694          for public access to a Transparent copy of the Document, and
3695          likewise the network locations given in the Document for
3696          previous versions it was based on.  These may be placed in
3697          the "History" section.  You may omit a network location for a
3698          work that was published at least four years before the
3699          Document itself, or if the original publisher of the version
3700          it refers to gives permission.
3701
3702       K. For any section Entitled "Acknowledgements" or "Dedications",
3703          Preserve the Title of the section, and preserve in the
3704          section all the substance and tone of each of the contributor
3705          acknowledgements and/or dedications given therein.
3706
3707       L. Preserve all the Invariant Sections of the Document,
3708          unaltered in their text and in their titles.  Section numbers
3709          or the equivalent are not considered part of the section
3710          titles.
3711
3712       M. Delete any section Entitled "Endorsements".  Such a section
3713          may not be included in the Modified Version.
3714
3715       N. Do not retitle any existing section to be Entitled
3716          "Endorsements" or to conflict in title with any Invariant
3717          Section.
3718
3719       O. Preserve any Warranty Disclaimers.
3720
3721     If the Modified Version includes new front-matter sections or
3722     appendices that qualify as Secondary Sections and contain no
3723     material copied from the Document, you may at your option
3724     designate some or all of these sections as invariant.  To do this,
3725     add their titles to the list of Invariant Sections in the Modified
3726     Version's license notice.  These titles must be distinct from any
3727     other section titles.
3728
3729     You may add a section Entitled "Endorsements", provided it contains
3730     nothing but endorsements of your Modified Version by various
3731     parties--for example, statements of peer review or that the text
3732     has been approved by an organization as the authoritative
3733     definition of a standard.
3734
3735     You may add a passage of up to five words as a Front-Cover Text,
3736     and a passage of up to 25 words as a Back-Cover Text, to the end
3737     of the list of Cover Texts in the Modified Version.  Only one
3738     passage of Front-Cover Text and one of Back-Cover Text may be
3739     added by (or through arrangements made by) any one entity.  If the
3740     Document already includes a cover text for the same cover,
3741     previously added by you or by arrangement made by the same entity
3742     you are acting on behalf of, you may not add another; but you may
3743     replace the old one, on explicit permission from the previous
3744     publisher that added the old one.
3745
3746     The author(s) and publisher(s) of the Document do not by this
3747     License give permission to use their names for publicity for or to
3748     assert or imply endorsement of any Modified Version.
3749
3750  5. COMBINING DOCUMENTS
3751
3752     You may combine the Document with other documents released under
3753     this License, under the terms defined in section 4 above for
3754     modified versions, provided that you include in the combination
3755     all of the Invariant Sections of all of the original documents,
3756     unmodified, and list them all as Invariant Sections of your
3757     combined work in its license notice, and that you preserve all
3758     their Warranty Disclaimers.
3759
3760     The combined work need only contain one copy of this License, and
3761     multiple identical Invariant Sections may be replaced with a single
3762     copy.  If there are multiple Invariant Sections with the same name
3763     but different contents, make the title of each such section unique
3764     by adding at the end of it, in parentheses, the name of the
3765     original author or publisher of that section if known, or else a
3766     unique number.  Make the same adjustment to the section titles in
3767     the list of Invariant Sections in the license notice of the
3768     combined work.
3769
3770     In the combination, you must combine any sections Entitled
3771     "History" in the various original documents, forming one section
3772     Entitled "History"; likewise combine any sections Entitled
3773     "Acknowledgements", and any sections Entitled "Dedications".  You
3774     must delete all sections Entitled "Endorsements."
3775
3776  6. COLLECTIONS OF DOCUMENTS
3777
3778     You may make a collection consisting of the Document and other
3779     documents released under this License, and replace the individual
3780     copies of this License in the various documents with a single copy
3781     that is included in the collection, provided that you follow the
3782     rules of this License for verbatim copying of each of the
3783     documents in all other respects.
3784
3785     You may extract a single document from such a collection, and
3786     distribute it individually under this License, provided you insert
3787     a copy of this License into the extracted document, and follow
3788     this License in all other respects regarding verbatim copying of
3789     that document.
3790
3791  7. AGGREGATION WITH INDEPENDENT WORKS
3792
3793     A compilation of the Document or its derivatives with other
3794     separate and independent documents or works, in or on a volume of
3795     a storage or distribution medium, is called an "aggregate" if the
3796     copyright resulting from the compilation is not used to limit the
3797     legal rights of the compilation's users beyond what the individual
3798     works permit.  When the Document is included in an aggregate, this
3799     License does not apply to the other works in the aggregate which
3800     are not themselves derivative works of the Document.
3801
3802     If the Cover Text requirement of section 3 is applicable to these
3803     copies of the Document, then if the Document is less than one half
3804     of the entire aggregate, the Document's Cover Texts may be placed
3805     on covers that bracket the Document within the aggregate, or the
3806     electronic equivalent of covers if the Document is in electronic
3807     form.  Otherwise they must appear on printed covers that bracket
3808     the whole aggregate.
3809
3810  8. TRANSLATION
3811
3812     Translation is considered a kind of modification, so you may
3813     distribute translations of the Document under the terms of section
3814     4.  Replacing Invariant Sections with translations requires special
3815     permission from their copyright holders, but you may include
3816     translations of some or all Invariant Sections in addition to the
3817     original versions of these Invariant Sections.  You may include a
3818     translation of this License, and all the license notices in the
3819     Document, and any Warranty Disclaimers, provided that you also
3820     include the original English version of this License and the
3821     original versions of those notices and disclaimers.  In case of a
3822     disagreement between the translation and the original version of
3823     this License or a notice or disclaimer, the original version will
3824     prevail.
3825
3826     If a section in the Document is Entitled "Acknowledgements",
3827     "Dedications", or "History", the requirement (section 4) to
3828     Preserve its Title (section 1) will typically require changing the
3829     actual title.
3830
3831  9. TERMINATION
3832
3833     You may not copy, modify, sublicense, or distribute the Document
3834     except as expressly provided for under this License.  Any other
3835     attempt to copy, modify, sublicense or distribute the Document is
3836     void, and will automatically terminate your rights under this
3837     License.  However, parties who have received copies, or rights,
3838     from you under this License will not have their licenses
3839     terminated so long as such parties remain in full compliance.
3840
3841 10. FUTURE REVISIONS OF THIS LICENSE
3842
3843     The Free Software Foundation may publish new, revised versions of
3844     the GNU Free Documentation License from time to time.  Such new
3845     versions will be similar in spirit to the present version, but may
3846     differ in detail to address new problems or concerns.  See
3847     `http://www.gnu.org/copyleft/'.
3848
3849     Each version of the License is given a distinguishing version
3850     number.  If the Document specifies that a particular numbered
3851     version of this License "or any later version" applies to it, you
3852     have the option of following the terms and conditions either of
3853     that specified version or of any later version that has been
3854     published (not as a draft) by the Free Software Foundation.  If
3855     the Document does not specify a version number of this License,
3856     you may choose any version ever published (not as a draft) by the
3857     Free Software Foundation.
3858
3859A.1.1 ADDENDUM: How to use this License for your documents
3860----------------------------------------------------------
3861
3862To use this License in a document you have written, include a copy of
3863the License in the document and put the following copyright and license
3864notices just after the title page:
3865
3866       Copyright (C)  YEAR  YOUR NAME.
3867       Permission is granted to copy, distribute and/or modify this document
3868       under the terms of the GNU Free Documentation License, Version 1.2
3869       or any later version published by the Free Software Foundation;
3870       with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
3871       Texts.  A copy of the license is included in the section entitled ``GNU
3872       Free Documentation License''.
3873
3874   If you have Invariant Sections, Front-Cover Texts and Back-Cover
3875Texts, replace the "with...Texts." line with this:
3876
3877         with the Invariant Sections being LIST THEIR TITLES, with
3878         the Front-Cover Texts being LIST, and with the Back-Cover Texts
3879         being LIST.
3880
3881   If you have Invariant Sections without Cover Texts, or some other
3882combination of the three, merge those two alternatives to suit the
3883situation.
3884
3885   If your document contains nontrivial examples of program code, we
3886recommend releasing these examples in parallel under your choice of
3887free software license, such as the GNU General Public License, to
3888permit their use in free software.
3889
3890
3891File: groff,  Node: Request Index,  Next: Escape Index,  Prev: Copying This Manual,  Up: Top
3892
3893Appendix B Request Index
3894************************
3895
3896Requests appear without the leading control character (normally either
3897`.' or `'').
3898
3899[index]
3900* Menu:
3901
3902* ab:                                    Debugging.           (line  40)
3903* ad:                                    Manipulating Filling and Adjusting.
3904                                                              (line  52)
3905* af:                                    Assigning Formats.   (line  13)
3906* aln:                                   Setting Registers.   (line  79)
3907* als:                                   Strings.             (line 224)
3908* am:                                    Writing Macros.      (line 107)
3909* am1:                                   Writing Macros.      (line 108)
3910* ami:                                   Writing Macros.      (line 109)
3911* ami1:                                  Writing Macros.      (line 110)
3912* as:                                    Strings.             (line 170)
3913* as1:                                   Strings.             (line 171)
3914* asciify:                               Diversions.          (line 195)
3915* backtrace:                             Debugging.           (line  94)
3916* bd:                                    Artificial Fonts.    (line  96)
3917* blm:                                   Blank Line Traps.    (line   7)
3918* box:                                   Diversions.          (line  25)
3919* boxa:                                  Diversions.          (line  26)
3920* bp:                                    Page Control.        (line   7)
3921* br:                                    Manipulating Filling and Adjusting.
3922                                                              (line  12)
3923* break:                                 while.               (line  73)
3924* brp:                                   Manipulating Filling and Adjusting.
3925                                                              (line 112)
3926* c2:                                    Character Translations.
3927                                                              (line  16)
3928* cc:                                    Character Translations.
3929                                                              (line  10)
3930* ce:                                    Manipulating Filling and Adjusting.
3931                                                              (line 189)
3932* cf:                                    I/O.                 (line  49)
3933* cflags:                                Using Symbols.       (line 241)
3934* ch:                                    Page Location Traps. (line 106)
3935* char:                                  Using Symbols.       (line 281)
3936* chop:                                  Strings.             (line 231)
3937* close:                                 I/O.                 (line 230)
3938* color:                                 Colors.              (line   7)
3939* composite:                             Using Symbols.       (line 197)
3940* continue:                              while.               (line  77)
3941* cp:                                    Implementation Differences.
3942                                                              (line  23)
3943* cs:                                    Artificial Fonts.    (line 127)
3944* cu:                                    Artificial Fonts.    (line  87)
3945* da:                                    Diversions.          (line  18)
3946* de:                                    Writing Macros.      (line  10)
3947* de1:                                   Writing Macros.      (line  11)
3948* defcolor:                              Colors.              (line  21)
3949* dei:                                   Writing Macros.      (line  12)
3950* dei1:                                  Writing Macros.      (line  13)
3951* di:                                    Diversions.          (line  17)
3952* do:                                    Implementation Differences.
3953                                                              (line  24)
3954* ds:                                    Strings.             (line  11)
3955* ds1:                                   Strings.             (line  12)
3956* dt:                                    Diversion Traps.     (line   7)
3957* ec:                                    Character Translations.
3958                                                              (line  47)
3959* ecr:                                   Character Translations.
3960                                                              (line  59)
3961* ecs:                                   Character Translations.
3962                                                              (line  58)
3963* el:                                    if-else.             (line  28)
3964* em:                                    End-of-input Traps.  (line   7)
3965* eo:                                    Character Translations.
3966                                                              (line  22)
3967* ev:                                    Environments.        (line  38)
3968* evc:                                   Environments.        (line  72)
3969* ex:                                    Debugging.           (line  45)
3970* fam:                                   Font Families.       (line  19)
3971* fc:                                    Fields.              (line  18)
3972* fchar:                                 Using Symbols.       (line 282)
3973* fcolor:                                Colors.              (line  85)
3974* fi:                                    Manipulating Filling and Adjusting.
3975                                                              (line  30)
3976* fl:                                    Debugging.           (line  85)
3977* fp:                                    Font Positions.      (line  11)
3978* fschar:                                Using Symbols.       (line 283)
3979* fspecial:                              Special Fonts.       (line  18)
3980* ft <1>:                                Font Positions.      (line  58)
3981* ft:                                    Changing Fonts.      (line   7)
3982* ftr:                                   Changing Fonts.      (line  53)
3983* gcolor:                                Colors.              (line  51)
3984* hc:                                    Manipulating Hyphenation.
3985                                                              (line 105)
3986* hcode:                                 Manipulating Hyphenation.
3987                                                              (line 174)
3988* hla:                                   Manipulating Hyphenation.
3989                                                              (line 253)
3990* hlm:                                   Manipulating Hyphenation.
3991                                                              (line  45)
3992* hpf:                                   Manipulating Hyphenation.
3993                                                              (line 114)
3994* hpfa:                                  Manipulating Hyphenation.
3995                                                              (line 115)
3996* hpfcode:                               Manipulating Hyphenation.
3997                                                              (line 116)
3998* hw:                                    Manipulating Hyphenation.
3999                                                              (line  61)
4000* hy:                                    Manipulating Hyphenation.
4001                                                              (line   9)
4002* hym:                                   Manipulating Hyphenation.
4003                                                              (line 209)
4004* hys:                                   Manipulating Hyphenation.
4005                                                              (line 224)
4006* ie:                                    if-else.             (line  27)
4007* if:                                    if-else.             (line  10)
4008* ig:                                    Comments.            (line  67)
4009* in:                                    Line Layout.         (line  91)
4010* it:                                    Input Line Traps.    (line   7)
4011* itc:                                   Input Line Traps.    (line   8)
4012* kern:                                  Ligatures and Kerning.
4013                                                              (line  41)
4014* lc:                                    Leaders.             (line  23)
4015* length:                                Strings.             (line 204)
4016* lf:                                    Debugging.           (line  10)
4017* lg:                                    Ligatures and Kerning.
4018                                                              (line  23)
4019* linetabs:                              Tabs and Fields.     (line 147)
4020* ll:                                    Line Layout.         (line 145)
4021* ls:                                    Manipulating Spacing.
4022                                                              (line  51)
4023* lt:                                    Page Layout.         (line  60)
4024* mc:                                    Miscellaneous.       (line  76)
4025* mk:                                    Page Motions.        (line  10)
4026* mso:                                   I/O.                 (line  41)
4027* na:                                    Manipulating Filling and Adjusting.
4028                                                              (line 104)
4029* ne:                                    Page Control.        (line  34)
4030* nf:                                    Manipulating Filling and Adjusting.
4031                                                              (line  41)
4032* nh:                                    Manipulating Hyphenation.
4033                                                              (line  37)
4034* nm:                                    Miscellaneous.       (line  10)
4035* nn:                                    Miscellaneous.       (line  72)
4036* nop:                                   if-else.             (line  24)
4037* nr <1>:                                Auto-increment.      (line  11)
4038* nr:                                    Setting Registers.   (line   9)
4039* nroff:                                 Troff and Nroff Mode.
4040                                                              (line  32)
4041* ns:                                    Manipulating Spacing.
4042                                                              (line 113)
4043* nx:                                    I/O.                 (line  74)
4044* open:                                  I/O.                 (line 198)
4045* opena:                                 I/O.                 (line 199)
4046* os:                                    Page Control.        (line  55)
4047* output:                                Diversions.          (line 180)
4048* pc:                                    Page Layout.         (line  89)
4049* pi:                                    I/O.                 (line 138)
4050* pl:                                    Page Layout.         (line  10)
4051* pm:                                    Debugging.           (line  64)
4052* pn:                                    Page Layout.         (line  77)
4053* pnr:                                   Debugging.           (line  75)
4054* po:                                    Line Layout.         (line  61)
4055* ps:                                    Changing Type Sizes. (line   7)
4056* psbb:                                  Miscellaneous.       (line 141)
4057* pso:                                   I/O.                 (line  30)
4058* ptr:                                   Debugging.           (line  79)
4059* pvs:                                   Changing Type Sizes. (line 133)
4060* rchar:                                 Using Symbols.       (line 340)
4061* rd:                                    I/O.                 (line  79)
4062* return:                                Writing Macros.      (line 143)
4063* rfschar:                               Using Symbols.       (line 341)
4064* rj:                                    Manipulating Filling and Adjusting.
4065                                                              (line 238)
4066* rm:                                    Strings.             (line 219)
4067* rn:                                    Strings.             (line 216)
4068* rnn:                                   Setting Registers.   (line  75)
4069* rr:                                    Setting Registers.   (line  71)
4070* rs:                                    Manipulating Spacing.
4071                                                              (line 114)
4072* rt:                                    Page Motions.        (line  11)
4073* schar:                                 Using Symbols.       (line 284)
4074* shc:                                   Manipulating Hyphenation.
4075                                                              (line 240)
4076* shift:                                 Parameters.          (line  30)
4077* sizes:                                 Changing Type Sizes. (line  69)
4078* so:                                    I/O.                 (line   9)
4079* sp:                                    Manipulating Spacing.
4080                                                              (line   7)
4081* special:                               Special Fonts.       (line  17)
4082* spreadwarn:                            Debugging.           (line 131)
4083* ss:                                    Manipulating Filling and Adjusting.
4084                                                              (line 134)
4085* sty:                                   Font Families.       (line  61)
4086* substring:                             Strings.             (line 188)
4087* sv:                                    Page Control.        (line  54)
4088* sy:                                    I/O.                 (line 160)
4089* ta:                                    Tabs and Fields.     (line  14)
4090* tc:                                    Tabs and Fields.     (line 139)
4091* ti:                                    Line Layout.         (line 117)
4092* tkf:                                   Ligatures and Kerning.
4093                                                              (line  60)
4094* tl:                                    Page Layout.         (line  35)
4095* tm:                                    Debugging.           (line  25)
4096* tm1:                                   Debugging.           (line  26)
4097* tmc:                                   Debugging.           (line  27)
4098* tr:                                    Character Translations.
4099                                                              (line 153)
4100* trf:                                   I/O.                 (line  48)
4101* trin:                                  Character Translations.
4102                                                              (line 154)
4103* trnt:                                  Character Translations.
4104                                                              (line 245)
4105* troff:                                 Troff and Nroff Mode.
4106                                                              (line  24)
4107* uf:                                    Artificial Fonts.    (line  91)
4108* ul:                                    Artificial Fonts.    (line  65)
4109* unformat:                              Diversions.          (line 215)
4110* vpt:                                   Page Location Traps. (line  17)
4111* vs:                                    Changing Type Sizes. (line  84)
4112* warn:                                  Debugging.           (line 154)
4113* warnscale:                             Debugging.           (line 127)
4114* wh:                                    Page Location Traps. (line  29)
4115* while:                                 while.               (line  10)
4116* write:                                 I/O.                 (line 210)
4117* writec:                                I/O.                 (line 211)
4118* writem:                                I/O.                 (line 221)
4119
4120
4121File: groff,  Node: Escape Index,  Next: Operator Index,  Prev: Request Index,  Up: Top
4122
4123Appendix C Escape Index
4124***********************
4125
4126Any escape sequence `\X' with X not in the list below emits a warning,
4127printing glyph X.
4128
4129[index]
4130* Menu:
4131
4132* \:                                     Using Symbols.       (line 139)
4133* \!:                                    Diversions.          (line 133)
4134* \":                                    Comments.            (line  10)
4135* \#:                                    Comments.            (line  50)
4136* \$:                                    Parameters.          (line  19)
4137* \$*:                                   Parameters.          (line  38)
4138* \$0:                                   Parameters.          (line  48)
4139* \$@:                                   Parameters.          (line  39)
4140* \%:                                    Manipulating Hyphenation.
4141                                                              (line  84)
4142* \&:                                    Ligatures and Kerning.
4143                                                              (line 102)
4144* \':                                    Using Symbols.       (line 229)
4145* \):                                    Ligatures and Kerning.
4146                                                              (line 131)
4147* \*:                                    Strings.             (line  13)
4148* \,:                                    Ligatures and Kerning.
4149                                                              (line  92)
4150* \-:                                    Using Symbols.       (line 238)
4151* \.:                                    Character Translations.
4152                                                              (line 126)
4153* \/:                                    Ligatures and Kerning.
4154                                                              (line  80)
4155* \0:                                    Page Motions.        (line 139)
4156* \<colon>:                              Manipulating Hyphenation.
4157                                                              (line  85)
4158* \<RET>:                                Line Control.        (line  43)
4159* \<SP>:                                 Page Motions.        (line 123)
4160* \?:                                    Diversions.          (line 134)
4161* \\:                                    Character Translations.
4162                                                              (line  68)
4163* \^:                                    Page Motions.        (line 135)
4164* \`:                                    Using Symbols.       (line 234)
4165* \a:                                    Leaders.             (line  18)
4166* \A:                                    Identifiers.         (line  55)
4167* \b:                                    Drawing Requests.    (line 223)
4168* \B:                                    Expressions.         (line  65)
4169* \C:                                    Using Symbols.       (line 191)
4170* \c:                                    Line Control.        (line  44)
4171* \D:                                    Drawing Requests.    (line  71)
4172* \d:                                    Page Motions.        (line 109)
4173* \E:                                    Character Translations.
4174                                                              (line  70)
4175* \e:                                    Character Translations.
4176                                                              (line  69)
4177* \f:                                    Font Positions.      (line  59)
4178* \F:                                    Font Families.       (line  21)
4179* \f:                                    Changing Fonts.      (line   8)
4180* \g:                                    Assigning Formats.   (line  75)
4181* \h:                                    Page Motions.        (line 112)
4182* \H:                                    Artificial Fonts.    (line  13)
4183* \k:                                    Page Motions.        (line 203)
4184* \L:                                    Drawing Requests.    (line  50)
4185* \l:                                    Drawing Requests.    (line  16)
4186* \M:                                    Colors.              (line  86)
4187* \m:                                    Colors.              (line  52)
4188* \N:                                    Using Symbols.       (line 207)
4189* \n <1>:                                Auto-increment.      (line  19)
4190* \n:                                    Interpolating Registers.
4191                                                              (line   9)
4192* \O:                                    Suppressing output.  (line   7)
4193* \o:                                    Page Motions.        (line 218)
4194* \p:                                    Manipulating Filling and Adjusting.
4195                                                              (line 113)
4196* \r:                                    Page Motions.        (line 103)
4197* \R:                                    Setting Registers.   (line  10)
4198* \s:                                    Changing Type Sizes. (line  10)
4199* \S:                                    Artificial Fonts.    (line  45)
4200* \t:                                    Tabs and Fields.     (line  10)
4201* \u:                                    Page Motions.        (line 106)
4202* \V:                                    I/O.                 (line 248)
4203* \v:                                    Page Motions.        (line  87)
4204* \w:                                    Page Motions.        (line 147)
4205* \X:                                    Postprocessor Access.
4206                                                              (line  11)
4207* \x:                                    Manipulating Spacing.
4208                                                              (line  71)
4209* \Y:                                    Postprocessor Access.
4210                                                              (line  25)
4211* \Z:                                    Page Motions.        (line 226)
4212* \z:                                    Page Motions.        (line 222)
4213* \{:                                    if-else.             (line  38)
4214* \|:                                    Page Motions.        (line 131)
4215* \}:                                    if-else.             (line  38)
4216* \~:                                    Page Motions.        (line 127)
4217
4218
4219File: groff,  Node: Operator Index,  Next: Register Index,  Prev: Escape Index,  Up: Top
4220
4221Appendix D Operator Index
4222*************************
4223
4224[index]
4225* Menu:
4226
4227* !:                                     Expressions.          (line 21)
4228* %:                                     Expressions.          (line  8)
4229* &:                                     Expressions.          (line 19)
4230* (:                                     Expressions.          (line 41)
4231* ):                                     Expressions.          (line 41)
4232* *:                                     Expressions.          (line  8)
4233* +:                                     Expressions.          (line  8)
4234* -:                                     Expressions.          (line  8)
4235* /:                                     Expressions.          (line  8)
4236* <:                                     Expressions.          (line 15)
4237* <=:                                    Expressions.          (line 15)
4238* <?:                                    Expressions.          (line 26)
4239* <colon>:                               Expressions.          (line 19)
4240* =:                                     Expressions.          (line 15)
4241* ==:                                    Expressions.          (line 15)
4242* >:                                     Expressions.          (line 15)
4243* >=:                                    Expressions.          (line 15)
4244* >?:                                    Expressions.          (line 26)
4245
4246
4247File: groff,  Node: Register Index,  Next: Macro Index,  Prev: Operator Index,  Up: Top
4248
4249Appendix E Register Index
4250*************************
4251
4252The macro package or program a specific register belongs to is appended
4253in brackets.
4254
4255   A register name `x' consisting of exactly one character can be
4256accessed as `\nx'.  A register name `xx' consisting of exactly two
4257characters can be accessed as `\n(xx'.  Register names `xxx' of any
4258length can be accessed as `\n[xxx]'.
4259
4260[index]
4261* Menu:
4262
4263* $$:                                    Built-in Registers.  (line  96)
4264* % <1>:                                 Page Control.        (line  10)
4265* %:                                     Page Layout.         (line  89)
4266* .$:                                    Parameters.          (line  10)
4267* .a:                                    Manipulating Spacing.
4268                                                              (line  72)
4269* .A:                                    Built-in Registers.  (line 103)
4270* .b:                                    Artificial Fonts.    (line  98)
4271* .C:                                    Implementation Differences.
4272                                                              (line  25)
4273* .c:                                    Built-in Registers.  (line  73)
4274* .cdp:                                  Environments.        (line  96)
4275* .ce:                                   Manipulating Filling and Adjusting.
4276                                                              (line 190)
4277* .cht:                                  Environments.        (line  95)
4278* .color:                                Colors.              (line   8)
4279* .csk:                                  Environments.        (line  97)
4280* .d:                                    Diversions.          (line  62)
4281* .ev:                                   Environments.        (line  39)
4282* .f:                                    Font Positions.      (line  12)
4283* .F:                                    Built-in Registers.  (line  12)
4284* .fam:                                  Font Families.       (line  20)
4285* .fn:                                   Font Families.       (line  24)
4286* .fp:                                   Font Positions.      (line  13)
4287* .g:                                    Built-in Registers.  (line  99)
4288* .h:                                    Diversions.          (line  69)
4289* .H:                                    Built-in Registers.  (line  15)
4290* .height:                               Artificial Fonts.    (line  16)
4291* .hla:                                  Manipulating Hyphenation.
4292                                                              (line 254)
4293* .hlc:                                  Manipulating Hyphenation.
4294                                                              (line  47)
4295* .hlm:                                  Manipulating Hyphenation.
4296                                                              (line  46)
4297* .hy:                                   Manipulating Hyphenation.
4298                                                              (line  10)
4299* .hym:                                  Manipulating Hyphenation.
4300                                                              (line 210)
4301* .hys:                                  Manipulating Hyphenation.
4302                                                              (line 225)
4303* .i:                                    Line Layout.         (line  94)
4304* .in:                                   Line Layout.         (line 120)
4305* .int:                                  Line Control.        (line  45)
4306* .j:                                    Manipulating Filling and Adjusting.
4307                                                              (line  53)
4308* .k:                                    Page Motions.        (line 214)
4309* .kern:                                 Ligatures and Kerning.
4310                                                              (line  42)
4311* .l:                                    Line Layout.         (line 148)
4312* .L:                                    Manipulating Spacing.
4313                                                              (line  52)
4314* .lg:                                   Ligatures and Kerning.
4315                                                              (line  24)
4316* .linetabs:                             Tabs and Fields.     (line 148)
4317* .ll:                                   Line Layout.         (line 149)
4318* .lt:                                   Page Layout.         (line  63)
4319* .M:                                    Colors.              (line  89)
4320* .m:                                    Colors.              (line  55)
4321* .n:                                    Environments.        (line 112)
4322* .ne:                                   Page Location Traps. (line 118)
4323* .ns:                                   Manipulating Spacing.
4324                                                              (line 115)
4325* .o:                                    Line Layout.         (line  64)
4326* .p:                                    Page Layout.         (line  13)
4327* .P:                                    Built-in Registers.  (line 108)
4328* .pe:                                   Page Location Traps. (line 139)
4329* .pn:                                   Page Layout.         (line  80)
4330* .ps:                                   Fractional Type Sizes.
4331                                                              (line  35)
4332* .psr:                                  Fractional Type Sizes.
4333                                                              (line  42)
4334* .pvs:                                  Changing Type Sizes. (line 136)
4335* .rj:                                   Manipulating Filling and Adjusting.
4336                                                              (line 239)
4337* .s:                                    Changing Type Sizes. (line  11)
4338* .slant:                                Artificial Fonts.    (line  46)
4339* .sr:                                   Fractional Type Sizes.
4340                                                              (line  43)
4341* .ss:                                   Manipulating Filling and Adjusting.
4342                                                              (line 135)
4343* .sss:                                  Manipulating Filling and Adjusting.
4344                                                              (line 136)
4345* .sty:                                  Changing Fonts.      (line  11)
4346* .t:                                    Page Location Traps. (line  97)
4347* .T:                                    Built-in Registers.  (line 114)
4348* .tabs:                                 Tabs and Fields.     (line  15)
4349* .trunc:                                Page Location Traps. (line 127)
4350* .u:                                    Manipulating Filling and Adjusting.
4351                                                              (line  31)
4352* .v:                                    Changing Type Sizes. (line  87)
4353* .V:                                    Built-in Registers.  (line  23)
4354* .vpt:                                  Page Location Traps. (line  18)
4355* .w:                                    Environments.        (line  94)
4356* .warn:                                 Debugging.           (line 155)
4357* .x:                                    Built-in Registers.  (line  85)
4358* .Y:                                    Built-in Registers.  (line  93)
4359* .y:                                    Built-in Registers.  (line  89)
4360* .z:                                    Diversions.          (line  61)
4361* c.:                                    Built-in Registers.  (line  74)
4362* ct:                                    Page Motions.        (line 152)
4363* dl:                                    Diversions.          (line  87)
4364* dn:                                    Diversions.          (line  86)
4365* dw:                                    Built-in Registers.  (line  39)
4366* dy:                                    Built-in Registers.  (line  42)
4367* FAM [ms]:                              ms Document Control Registers.
4368                                                              (line 110)
4369* FF [ms]:                               ms Document Control Registers.
4370                                                              (line 184)
4371* FI [ms]:                               ms Document Control Registers.
4372                                                              (line 177)
4373* FL [ms]:                               ms Document Control Registers.
4374                                                              (line 170)
4375* FM [ms]:                               ms Document Control Registers.
4376                                                              (line  47)
4377* FPD [ms]:                              ms Document Control Registers.
4378                                                              (line 221)
4379* FPS [ms]:                              ms Document Control Registers.
4380                                                              (line 204)
4381* FVS [ms]:                              ms Document Control Registers.
4382                                                              (line 212)
4383* GROWPS [ms]:                           ms Document Control Registers.
4384                                                              (line  88)
4385* GS [ms]:                               Differences from AT&T ms.
4386                                                              (line  46)
4387* HM [ms]:                               ms Document Control Registers.
4388                                                              (line  40)
4389* HORPHANS [ms]:                         ms Document Control Registers.
4390                                                              (line 154)
4391* hours:                                 Built-in Registers.  (line  35)
4392* hp:                                    Page Motions.        (line 211)
4393* HY [ms]:                               ms Document Control Registers.
4394                                                              (line 101)
4395* LL [ms]:                               ms Document Control Registers.
4396                                                              (line  25)
4397* llx:                                   Miscellaneous.       (line 142)
4398* lly:                                   Miscellaneous.       (line 143)
4399* ln:                                    Built-in Registers.  (line  79)
4400* LT [ms]:                               ms Document Control Registers.
4401                                                              (line  32)
4402* MINGW [ms] <1>:                        Additional ms Macros.
4403                                                              (line  28)
4404* MINGW [ms]:                            ms Document Control Registers.
4405                                                              (line 231)
4406* minutes:                               Built-in Registers.  (line  31)
4407* mo:                                    Built-in Registers.  (line  45)
4408* nl:                                    Page Control.        (line  68)
4409* opmaxx:                                Suppressing output.  (line  19)
4410* opmaxy:                                Suppressing output.  (line  19)
4411* opminx:                                Suppressing output.  (line  19)
4412* opminy:                                Suppressing output.  (line  19)
4413* PD [ms]:                               ms Document Control Registers.
4414                                                              (line 127)
4415* PI [ms]:                               ms Document Control Registers.
4416                                                              (line 120)
4417* PO [ms]:                               ms Document Control Registers.
4418                                                              (line  16)
4419* PORPHANS [ms]:                         ms Document Control Registers.
4420                                                              (line 142)
4421* PS [ms]:                               ms Document Control Registers.
4422                                                              (line  57)
4423* ps4html [grohtml]:                     grohtml specific registers and strings.
4424                                                              (line   7)
4425* PSINCR [ms]:                           ms Document Control Registers.
4426                                                              (line  77)
4427* QI [ms]:                               ms Document Control Registers.
4428                                                              (line 134)
4429* rsb:                                   Page Motions.        (line 151)
4430* rst:                                   Page Motions.        (line 150)
4431* sb:                                    Page Motions.        (line 149)
4432* seconds:                               Built-in Registers.  (line  26)
4433* skw:                                   Page Motions.        (line 154)
4434* slimit:                                Debugging.           (line 119)
4435* ssc:                                   Page Motions.        (line 153)
4436* st:                                    Page Motions.        (line 148)
4437* systat:                                I/O.                 (line 161)
4438* urx:                                   Miscellaneous.       (line 144)
4439* ury:                                   Miscellaneous.       (line 145)
4440* VS [ms]:                               ms Document Control Registers.
4441                                                              (line  67)
4442* year:                                  Built-in Registers.  (line  48)
4443* yr:                                    Built-in Registers.  (line  51)
4444
4445
4446File: groff,  Node: Macro Index,  Next: String Index,  Prev: Register Index,  Up: Top
4447
4448Appendix F Macro Index
4449**********************
4450
4451The macro package a specific macro belongs to is appended in brackets.
4452They appear without the leading control character (normally `.').
4453
4454[index]
4455* Menu:
4456
4457* 1C [ms]:                               ms Multiple Columns. (line  13)
4458* 2C [ms]:                               ms Multiple Columns. (line  16)
4459* [ [ms]:                                ms Insertions.       (line  33)
4460* ] [ms]:                                ms Insertions.       (line  34)
4461* AB [ms]:                               ms Cover Page Macros.
4462                                                              (line  60)
4463* AE [ms]:                               ms Cover Page Macros.
4464                                                              (line  65)
4465* AI [ms]:                               ms Cover Page Macros.
4466                                                              (line  56)
4467* AM [ms] <1>:                           Additional ms Macros.
4468                                                              (line  10)
4469* AM [ms]:                               ms Strings and Special Characters.
4470                                                              (line  51)
4471* AT [man]:                              Miscellaneous man macros.
4472                                                              (line  26)
4473* AU [ms]:                               ms Cover Page Macros.
4474                                                              (line  38)
4475* B [man]:                               Man font macros.     (line  48)
4476* B [ms]:                                Highlighting in ms.  (line  10)
4477* B1 [ms]:                               ms Displays and Keeps.
4478                                                              (line  94)
4479* B2 [ms]:                               ms Displays and Keeps.
4480                                                              (line  95)
4481* BD [ms]:                               ms Displays and Keeps.
4482                                                              (line  31)
4483* BI [man]:                              Man font macros.     (line  18)
4484* BI [ms]:                               Highlighting in ms.  (line  39)
4485* BR [man]:                              Man font macros.     (line  40)
4486* BT [man]:                              Optional man extensions.
4487                                                              (line  21)
4488* BX [ms]:                               Highlighting in ms.  (line  43)
4489* CD [ms]:                               ms Displays and Keeps.
4490                                                              (line  41)
4491* CT [man]:                              Optional man extensions.
4492                                                              (line  36)
4493* CW [man]:                              Optional man extensions.
4494                                                              (line  39)
4495* CW [ms] <1>:                           Additional ms Macros.
4496                                                              (line  19)
4497* CW [ms]:                               Highlighting in ms.  (line  35)
4498* DA [ms]:                               ms Cover Page Macros.
4499                                                              (line  23)
4500* De [man]:                              Optional man extensions.
4501                                                              (line  45)
4502* De [ms]:                               ms Displays and Keeps.
4503                                                              (line  57)
4504* DE [ms]:                               ms Displays and Keeps.
4505                                                              (line  16)
4506* Ds [man]:                              Optional man extensions.
4507                                                              (line  42)
4508* DS [ms]:                               Additional ms Macros.
4509                                                              (line  14)
4510* Ds [ms]:                               ms Displays and Keeps.
4511                                                              (line  56)
4512* DS [ms]:                               ms Displays and Keeps.
4513                                                              (line  14)
4514* DT [man]:                              Miscellaneous man macros.
4515                                                              (line  10)
4516* EE [man]:                              Optional man extensions.
4517                                                              (line  52)
4518* EF [ms]:                               ms Headers and Footers.
4519                                                              (line  26)
4520* EH [ms]:                               ms Headers and Footers.
4521                                                              (line  24)
4522* EN [ms]:                               ms Insertions.       (line  28)
4523* EQ [ms]:                               ms Insertions.       (line  27)
4524* EX [man]:                              Optional man extensions.
4525                                                              (line  48)
4526* FE [ms]:                               ms Footnotes.        (line  15)
4527* FS [ms]:                               ms Footnotes.        (line  14)
4528* G [man]:                               Optional man extensions.
4529                                                              (line  55)
4530* GL [man]:                              Optional man extensions.
4531                                                              (line  60)
4532* HB [man]:                              Optional man extensions.
4533                                                              (line  65)
4534* HP [man]:                              Man usage.           (line  98)
4535* I [man]:                               Man font macros.     (line  53)
4536* I [ms]:                                Highlighting in ms.  (line  31)
4537* IB [man]:                              Man font macros.     (line  28)
4538* ID [ms]:                               ms Displays and Keeps.
4539                                                              (line  23)
4540* IP [man]:                              Man usage.           (line  78)
4541* IP [ms]:                               Lists in ms.         (line   9)
4542* IR [man]:                              Man font macros.     (line  36)
4543* IX [ms]:                               Additional ms Macros.
4544                                                              (line  22)
4545* KE [ms]:                               ms Displays and Keeps.
4546                                                              (line  73)
4547* KF [ms]:                               ms Displays and Keeps.
4548                                                              (line  77)
4549* KS [ms]:                               ms Displays and Keeps.
4550                                                              (line  72)
4551* LD [ms]:                               ms Displays and Keeps.
4552                                                              (line  15)
4553* LG [ms]:                               Highlighting in ms.  (line  52)
4554* LP [man]:                              Man usage.           (line  68)
4555* LP [ms]:                               Paragraphs in ms.    (line  10)
4556* MC [ms]:                               ms Multiple Columns. (line  19)
4557* MS [man]:                              Optional man extensions.
4558                                                              (line  73)
4559* ND [ms]:                               ms Cover Page Macros.
4560                                                              (line  28)
4561* NE [man]:                              Optional man extensions.
4562                                                              (line  85)
4563* NH [ms]:                               Headings in ms.      (line  13)
4564* NL [ms]:                               Highlighting in ms.  (line  64)
4565* NT [man]:                              Optional man extensions.
4566                                                              (line  78)
4567* OF [ms]:                               ms Headers and Footers.
4568                                                              (line  25)
4569* OH [ms]:                               ms Headers and Footers.
4570                                                              (line  23)
4571* P [man]:                               Man usage.           (line  70)
4572* P1 [ms]:                               ms Cover Page Macros.
4573                                                              (line  19)
4574* PD [man]:                              Miscellaneous man macros.
4575                                                              (line  15)
4576* PE [ms]:                               ms Insertions.       (line  21)
4577* Pn [man]:                              Optional man extensions.
4578                                                              (line  92)
4579* PN [man]:                              Optional man extensions.
4580                                                              (line  88)
4581* PP [man]:                              Man usage.           (line  69)
4582* PP [ms]:                               Paragraphs in ms.    (line   9)
4583* PS [ms]:                               ms Insertions.       (line  20)
4584* PT [man]:                              Optional man extensions.
4585                                                              (line  16)
4586* PX [ms]:                               ms TOC.              (line  65)
4587* QP [ms]:                               Paragraphs in ms.    (line  13)
4588* R [man]:                               Optional man extensions.
4589                                                              (line  98)
4590* R [ms]:                                Highlighting in ms.  (line  27)
4591* RB [man]:                              Man font macros.     (line  44)
4592* RD [ms]:                               ms Displays and Keeps.
4593                                                              (line  49)
4594* RE [man]:                              Man usage.           (line 115)
4595* RE [ms]:                               Indentation values in ms.
4596                                                              (line  12)
4597* RI [man]:                              Man font macros.     (line  32)
4598* RN [man]:                              Optional man extensions.
4599                                                              (line 101)
4600* RP [ms]:                               ms Cover Page Macros.
4601                                                              (line  10)
4602* RS [man]:                              Man usage.           (line 106)
4603* RS [ms]:                               Indentation values in ms.
4604                                                              (line  11)
4605* SB [man]:                              Man font macros.     (line  14)
4606* SH [man]:                              Man usage.           (line  32)
4607* SH [ms]:                               Headings in ms.      (line  43)
4608* SM [man]:                              Man font macros.     (line  10)
4609* SM [ms]:                               Highlighting in ms.  (line  58)
4610* SS [man]:                              Man usage.           (line  41)
4611* TA [ms]:                               Tabstops in ms.      (line  10)
4612* TB [man]:                              Optional man extensions.
4613                                                              (line  70)
4614* TC [ms]:                               ms TOC.              (line  55)
4615* TE [ms]:                               ms Insertions.       (line  12)
4616* TH [man]:                              Man usage.           (line  11)
4617* TL [ms]:                               ms Cover Page Macros.
4618                                                              (line  33)
4619* TP [man]:                              Man usage.           (line  49)
4620* TS [ms]:                               ms Insertions.       (line  11)
4621* UC [man]:                              Miscellaneous man macros.
4622                                                              (line  43)
4623* UL [ms]:                               Highlighting in ms.  (line  47)
4624* VE [man]:                              Optional man extensions.
4625                                                              (line 108)
4626* VS [man]:                              Optional man extensions.
4627                                                              (line 104)
4628* XA [ms]:                               ms TOC.              (line  13)
4629* XE [ms]:                               ms TOC.              (line  14)
4630* XP [ms]:                               Paragraphs in ms.    (line  18)
4631* XS [ms]:                               ms TOC.              (line  12)
4632
4633
4634File: groff,  Node: String Index,  Next: Glyph Name Index,  Prev: Macro Index,  Up: Top
4635
4636Appendix G String Index
4637***********************
4638
4639The macro package or program a specific string belongs to is appended in
4640brackets.
4641
4642   A string name `x' consisting of exactly one character can be
4643accessed as `\*x'.  A string name `xx' consisting of exactly two
4644characters can be accessed as `\*(xx'.  String names `xxx' of any
4645length can be accessed as `\*[xxx]'.
4646
4647[index]
4648* Menu:
4649
4650* ! [ms]:                                ms Strings and Special Characters.
4651                                                              (line 101)
4652* ' [ms]:                                ms Strings and Special Characters.
4653                                                              (line  65)
4654* * [ms]:                                ms Footnotes.        (line  11)
4655* , [ms]:                                ms Strings and Special Characters.
4656                                                              (line  74)
4657* - [ms]:                                ms Strings and Special Characters.
4658                                                              (line  41)
4659* . [ms]:                                ms Strings and Special Characters.
4660                                                              (line  89)
4661* .T:                                    Built-in Registers.  (line 119)
4662* 3 [ms]:                                ms Strings and Special Characters.
4663                                                              (line 107)
4664* 8 [ms]:                                ms Strings and Special Characters.
4665                                                              (line 104)
4666* ? [ms]:                                ms Strings and Special Characters.
4667                                                              (line  98)
4668* \*[<colon>] [ms]:                      ms Strings and Special Characters.
4669                                                              (line  80)
4670* ^ [ms]:                                ms Strings and Special Characters.
4671                                                              (line  71)
4672* _ [ms]:                                ms Strings and Special Characters.
4673                                                              (line  86)
4674* ` [ms]:                                ms Strings and Special Characters.
4675                                                              (line  68)
4676* ABSTRACT [ms]:                         ms Strings and Special Characters.
4677                                                              (line  15)
4678* Ae [ms]:                               ms Strings and Special Characters.
4679                                                              (line 128)
4680* ae [ms]:                               ms Strings and Special Characters.
4681                                                              (line 125)
4682* CF [ms]:                               ms Headers and Footers.
4683                                                              (line  16)
4684* CH [ms]:                               ms Headers and Footers.
4685                                                              (line  11)
4686* d- [ms]:                               ms Strings and Special Characters.
4687                                                              (line 119)
4688* D- [ms]:                               ms Strings and Special Characters.
4689                                                              (line 116)
4690* HF [man]:                              Predefined man strings.
4691                                                              (line  12)
4692* LF [ms]:                               ms Headers and Footers.
4693                                                              (line  15)
4694* LH [ms]:                               ms Headers and Footers.
4695                                                              (line  10)
4696* lq [man]:                              Predefined man strings.
4697                                                              (line  21)
4698* MONTH1 [ms]:                           ms Strings and Special Characters.
4699                                                              (line  23)
4700* MONTH10 [ms]:                          ms Strings and Special Characters.
4701                                                              (line  32)
4702* MONTH11 [ms]:                          ms Strings and Special Characters.
4703                                                              (line  33)
4704* MONTH12 [ms]:                          ms Strings and Special Characters.
4705                                                              (line  34)
4706* MONTH2 [ms]:                           ms Strings and Special Characters.
4707                                                              (line  24)
4708* MONTH3 [ms]:                           ms Strings and Special Characters.
4709                                                              (line  25)
4710* MONTH4 [ms]:                           ms Strings and Special Characters.
4711                                                              (line  26)
4712* MONTH5 [ms]:                           ms Strings and Special Characters.
4713                                                              (line  27)
4714* MONTH6 [ms]:                           ms Strings and Special Characters.
4715                                                              (line  28)
4716* MONTH7 [ms]:                           ms Strings and Special Characters.
4717                                                              (line  29)
4718* MONTH8 [ms]:                           ms Strings and Special Characters.
4719                                                              (line  30)
4720* MONTH9 [ms]:                           ms Strings and Special Characters.
4721                                                              (line  31)
4722* o [ms]:                                ms Strings and Special Characters.
4723                                                              (line  92)
4724* q [ms]:                                ms Strings and Special Characters.
4725                                                              (line 122)
4726* Q [ms]:                                ms Strings and Special Characters.
4727                                                              (line  44)
4728* R [man]:                               Predefined man strings.
4729                                                              (line  15)
4730* REFERENCES [ms]:                       ms Strings and Special Characters.
4731                                                              (line  11)
4732* RF [ms]:                               ms Headers and Footers.
4733                                                              (line  17)
4734* RH [ms]:                               ms Headers and Footers.
4735                                                              (line  12)
4736* rq [man]:                              Predefined man strings.
4737                                                              (line  22)
4738* S [man]:                               Predefined man strings.
4739                                                              (line   9)
4740* SN [ms]:                               Headings in ms.      (line  22)
4741* SN-DOT [ms]:                           Headings in ms.      (line  23)
4742* SN-NO-DOT [ms]:                        Headings in ms.      (line  24)
4743* th [ms]:                               ms Strings and Special Characters.
4744                                                              (line 113)
4745* Th [ms]:                               ms Strings and Special Characters.
4746                                                              (line 110)
4747* Tm [man]:                              Predefined man strings.
4748                                                              (line  18)
4749* TOC [ms]:                              ms Strings and Special Characters.
4750                                                              (line  19)
4751* U [ms]:                                ms Strings and Special Characters.
4752                                                              (line  45)
4753* v [ms]:                                ms Strings and Special Characters.
4754                                                              (line  83)
4755* www-image-template [grohtml]:          grohtml specific registers and strings.
4756                                                              (line   8)
4757* { [ms]:                                Highlighting in ms.  (line  68)
4758* } [ms]:                                Highlighting in ms.  (line  69)
4759* ~ [ms]:                                ms Strings and Special Characters.
4760                                                              (line  77)
4761
4762
4763File: groff,  Node: Glyph Name Index,  Next: Font File Keyword Index,  Prev: String Index,  Up: Top
4764
4765Appendix H Glyph Name Index
4766***************************
4767
4768A glyph name `xx' consisting of exactly two characters can be accessed
4769as `\(xx'.  Glyph names `xxx' of any length can be accessed as `\[xxx]'.
4770
4771
4772File: groff,  Node: Font File Keyword Index,  Next: Program and File Index,  Prev: Glyph Name Index,  Up: Top
4773
4774Appendix I Font File Keyword Index
4775**********************************
4776
4777[index]
4778* Menu:
4779
4780* #:                                     Font File Format.    (line  36)
4781* ---:                                   Font File Format.    (line  51)
4782* biggestfont:                           DESC File Format.    (line 109)
4783* charset <1>:                           Font File Format.    (line  44)
4784* charset:                               DESC File Format.    (line 101)
4785* family <1>:                            DESC File Format.    (line  64)
4786* family <2>:                            Font Positions.      (line  61)
4787* family:                                Changing Fonts.      (line  11)
4788* fonts <1>:                             DESC File Format.    (line  58)
4789* fonts <2>:                             Special Fonts.       (line  18)
4790* fonts:                                 Using Symbols.       (line  15)
4791* hor:                                   DESC File Format.    (line  14)
4792* kernpairs:                             Font File Format.    (line 135)
4793* ligatures:                             Font File Format.    (line  22)
4794* name:                                  Font File Format.    (line  12)
4795* papersize:                             DESC File Format.    (line  72)
4796* pass_filenames:                        DESC File Format.    (line  92)
4797* postpro:                               DESC File Format.    (line  36)
4798* prepro:                                DESC File Format.    (line  32)
4799* print:                                 DESC File Format.    (line  97)
4800* res:                                   DESC File Format.    (line  11)
4801* sizes:                                 DESC File Format.    (line  49)
4802* sizescale:                             DESC File Format.    (line  22)
4803* slant:                                 Font File Format.    (line  18)
4804* spacewidth:                            Font File Format.    (line  15)
4805* spare1:                                DESC File Format.    (line 109)
4806* spare2:                                DESC File Format.    (line 109)
4807* special <1>:                           Font File Format.    (line  28)
4808* special:                               Artificial Fonts.    (line 116)
4809* styles <1>:                            DESC File Format.    (line  55)
4810* styles <2>:                            Font Positions.      (line  61)
4811* styles <3>:                            Font Families.       (line  76)
4812* styles:                                Changing Fonts.      (line  11)
4813* tcommand:                              DESC File Format.    (line  45)
4814* unitwidth:                             DESC File Format.    (line  28)
4815* use_charnames_in_special <1>:          DESC File Format.    (line  67)
4816* use_charnames_in_special:              Postprocessor Access.
4817                                                              (line  17)
4818* vert:                                  DESC File Format.    (line  18)
4819
4820
4821File: groff,  Node: Program and File Index,  Next: Concept Index,  Prev: Font File Keyword Index,  Up: Top
4822
4823Appendix J Program and File Index
4824*********************************
4825
4826[index]
4827* Menu:
4828
4829* an.tmac:                               man.                 (line   6)
4830* changebar:                             Miscellaneous.       (line 111)
4831* composite.tmac:                        Using Symbols.       (line 197)
4832* cp1047.tmac:                           Input Encodings.     (line   9)
4833* DESC <1>:                              Special Fonts.       (line  18)
4834* DESC <2>:                              Using Symbols.       (line  15)
4835* DESC <3>:                              Font Positions.      (line  61)
4836* DESC <4>:                              Font Families.       (line  76)
4837* DESC:                                  Changing Fonts.      (line  11)
4838* DESC file format:                      DESC File Format.    (line   6)
4839* DESC, and font mounting:               Font Positions.      (line  37)
4840* DESC, and use_charnames_in_special:    Postprocessor Access.
4841                                                              (line  17)
4842* ditroff:                               History.             (line  58)
4843* ec.tmac:                               Input Encodings.     (line  41)
4844* eqn:                                   ms Insertions.       (line   7)
4845* freeeuro.pfa:                          Input Encodings.     (line  41)
4846* geqn:                                  Groff Options.       (line   6)
4847* geqn, invocation in manual pages:      Preprocessors in man pages.
4848                                                              (line  12)
4849* ggrn:                                  Groff Options.       (line   6)
4850* gpic:                                  Groff Options.       (line   6)
4851* grap:                                  Groff Options.       (line   6)
4852* grefer:                                Groff Options.       (line   6)
4853* grefer, invocation in manual pages:    Preprocessors in man pages.
4854                                                              (line  12)
4855* groff:                                 Groff Options.       (line   6)
4856* grog:                                  grog.                (line   6)
4857* grohtml:                               Miscellaneous man macros.
4858                                                              (line   6)
4859* gsoelim:                               Groff Options.       (line   6)
4860* gtbl:                                  Groff Options.       (line   6)
4861* gtbl, invocation in manual pages:      Preprocessors in man pages.
4862                                                              (line  12)
4863* gtroff:                                Groff Options.       (line   6)
4864* hyphen.us:                             Manipulating Hyphenation.
4865                                                              (line 161)
4866* hyphenex.us:                           Manipulating Hyphenation.
4867                                                              (line 161)
4868* latin1.tmac:                           Input Encodings.     (line  14)
4869* latin2.tmac:                           Input Encodings.     (line  18)
4870* latin9.tmac:                           Input Encodings.     (line  23)
4871* makeindex:                             Indices.             (line  10)
4872* man, invocation of preprocessors:      Preprocessors in man pages.
4873                                                              (line  12)
4874* man-old.tmac:                          man.                 (line   6)
4875* man.local <1>:                         Optional man extensions.
4876                                                              (line   6)
4877* man.local:                             Man usage.           (line   6)
4878* man.tmac:                              man.                 (line   6)
4879* man.ultrix:                            Optional man extensions.
4880                                                              (line  30)
4881* nrchbar:                               Miscellaneous.       (line 111)
4882* papersize.tmac:                        Paper Size.          (line  16)
4883* perl:                                  I/O.                 (line 171)
4884* pic:                                   ms Insertions.       (line   7)
4885* post-grohtml:                          Groff Options.       (line 165)
4886* pre-grohtml:                           Groff Options.       (line 165)
4887* refer:                                 ms Insertions.       (line   7)
4888* soelim:                                Debugging.           (line  10)
4889* tbl:                                   ms Insertions.       (line   7)
4890* trace.tmac:                            Writing Macros.      (line 101)
4891* troffrc <1>:                           Line Layout.         (line  64)
4892* troffrc <2>:                           Troff and Nroff Mode.
4893                                                              (line  24)
4894* troffrc <3>:                           Manipulating Hyphenation.
4895                                                              (line 161)
4896* troffrc <4>:                           Paper Size.          (line  16)
4897* troffrc:                               Groff Options.       (line  80)
4898* troffrc-end <1>:                       Troff and Nroff Mode.
4899                                                              (line  24)
4900* troffrc-end <2>:                       Manipulating Hyphenation.
4901                                                              (line 161)
4902* troffrc-end:                           Groff Options.       (line  80)
4903* tty.tmac:                              Troff and Nroff Mode.
4904                                                              (line  32)
4905
4906
4907
4908Local Variables:
4909coding: iso-8859-1
4910End: