ftok.c 1.1 KB

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  1. /* Copyright (C) 1995-2019 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.
  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. #include <sys/ipc.h>
  16. #include <sys/stat.h>
  17. key_t
  18. ftok (const char *pathname, int proj_id)
  19. {
  20. struct stat64 st;
  21. key_t key;
  22. if (__xstat64 (_STAT_VER, pathname, &st) < 0)
  23. return (key_t) -1;
  24. key = ((st.st_ino & 0xffff) | ((st.st_dev & 0xff) << 16)
  25. | ((proj_id & 0xff) << 24));
  26. return key;
  27. }