/bin/stty/util.c

https://bitbucket.org/freebsd/freebsd-head/ · C · 64 lines · 24 code · 6 blank · 34 comment · 4 complexity · 9a177efd399a9ecaf2ca9b02706fe8b9 MD5 · raw file

  1. /*-
  2. * Copyright (c) 1991, 1993, 1994
  3. * The Regents of the University of California. All rights reserved.
  4. *
  5. * Redistribution and use in source and binary forms, with or without
  6. * modification, are permitted provided that the following conditions
  7. * are met:
  8. * 1. Redistributions of source code must retain the above copyright
  9. * notice, this list of conditions and the following disclaimer.
  10. * 2. Redistributions in binary form must reproduce the above copyright
  11. * notice, this list of conditions and the following disclaimer in the
  12. * documentation and/or other materials provided with the distribution.
  13. * 4. Neither the name of the University nor the names of its contributors
  14. * may be used to endorse or promote products derived from this software
  15. * without specific prior written permission.
  16. *
  17. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27. * SUCH DAMAGE.
  28. */
  29. #ifndef lint
  30. #if 0
  31. static char sccsid[] = "@(#)util.c 8.3 (Berkeley) 4/2/94";
  32. #endif
  33. #endif /* not lint */
  34. #include <sys/cdefs.h>
  35. __FBSDID("$FreeBSD$");
  36. #include <sys/types.h>
  37. #include <sys/stat.h>
  38. #include <err.h>
  39. #include <stdio.h>
  40. #include <stdlib.h>
  41. #include <unistd.h>
  42. #include "stty.h"
  43. #include "extern.h"
  44. /*
  45. * Gross, but since we're changing the control descriptor from 1 to 0, most
  46. * users will be probably be doing "stty > /dev/sometty" by accident. If 1
  47. * and 2 are both ttys, but not the same, assume that 1 was incorrectly
  48. * redirected.
  49. */
  50. void
  51. checkredirect(void)
  52. {
  53. struct stat sb1, sb2;
  54. if (isatty(STDOUT_FILENO) && isatty(STDERR_FILENO) &&
  55. !fstat(STDOUT_FILENO, &sb1) && !fstat(STDERR_FILENO, &sb2) &&
  56. (sb1.st_rdev != sb2.st_rdev))
  57. warnx("stdout appears redirected, but stdin is the control descriptor");
  58. }