semaphore.h 1.2 KB

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  1. /* Copyright (C) 2002-2019 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. #ifndef _SEMAPHORE_H
  16. # error "Never use <bits/semaphore.h> directly; include <semaphore.h> instead."
  17. #endif
  18. #include <bits/wordsize.h>
  19. #if __WORDSIZE == 64
  20. # define __SIZEOF_SEM_T 32
  21. #else
  22. # define __SIZEOF_SEM_T 16
  23. #endif
  24. /* Value returned if `sem_open' failed. */
  25. #define SEM_FAILED ((sem_t *) 0)
  26. typedef union
  27. {
  28. char __size[__SIZEOF_SEM_T];
  29. long int __align;
  30. } sem_t;