/share/man/man3/end.3

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32.\"	@(#)end.3	6.4 (Berkeley) 1/24/94
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35.Dd August 28, 2000
36.Dt END 3
37.Os
38.Sh NAME
39.Nm end ,
40.Nm etext ,
41.Nm edata
42.Nd end boundaries of image segments
43.Sh SYNOPSIS
44.Vt extern end ;
45.Vt extern etext ;
46.Vt extern edata ;
47.Sh DESCRIPTION
48The globals
49.Va end , etext
50and
51.Va edata
52are program segment end addresses.
53.Pp
54.Va etext
55is the first address after the end of the text segment.
56.Pp
57.Va edata
58is the first address after the end of the initialized data segment.
59.Pp
60.Va end
61is the first address after the end of the data segment
62.Pq Tn BSS
63when the program is loaded.
64Use the
65.Xr sbrk 2
66.\".Fn sbrk 0
67system call with zero as its argument to find the current end of the
68data segment.
69.Sh SEE ALSO
70.Xr sbrk 2 ,
71.Xr malloc 3 ,
72.Xr a.out 5
73.Sh HISTORY
74An
75.Nm
76manual page appeared in
77.At v6 .
78.Sh BUGS
79Traditionally, no variable existed that pointed to the start of the
80text segment because the text segment always started at address zero.
81Although it is no longer valid to make this assumption, no
82variable similar to the ones documented above exists to point to the
83start of the text segment.