sigblock.c 1.3 KB

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  1. /* Copyright (C) 1991 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. The GNU C Library is free software; you can redistribute it and/or
  4. modify it under the terms of the GNU Library General Public License as
  5. published by the Free Software Foundation; either version 2 of the
  6. License, or (at your option) any later version.
  7. The GNU C Library is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  10. Library General Public License for more details.
  11. You should have received a copy of the GNU Library General Public
  12. License along with the GNU C Library; see the file COPYING.LIB. If
  13. not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  14. Cambridge, MA 02139, USA. */
  15. #include <errno.h>
  16. #define __USE_BSD
  17. #include <signal.h>
  18. /* Block signals in MASK, returning the old mask. */
  19. int sigblock (int mask)
  20. {
  21. register int sig;
  22. sigset_t set, oset;
  23. if (sigemptyset(&set) < 0)
  24. return -1;
  25. for (sig = 1; sig < NSIG; ++sig)
  26. if ((mask & sigmask(sig)) && sigaddset(&set, sig) < 0)
  27. return -1;
  28. if (sigprocmask(SIG_BLOCK, &set, &oset) < 0)
  29. return -1;
  30. mask = 0;
  31. for (sig = 1; sig < NSIG; ++sig)
  32. if (sigismember(&oset, sig))
  33. mask |= sigmask(sig);
  34. return mask;
  35. }