getpagesize.c 1.5 KB

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  1. /* Copyright (C) 1991,1992,1995-1997,2000,2002 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 Lesser General Public
  5. License as published by the Free Software Foundation; either
  6. version 2.1 of the 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. Lesser General Public License for more details.
  11. You should have received a copy of the GNU Lesser General Public
  12. License along with the GNU C Library; if not, write to the Free
  13. Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  14. 02111-1307 USA. */
  15. #include <unistd.h>
  16. #include <features.h>
  17. #include <sys/param.h>
  18. extern size_t __pagesize;
  19. /* Return the system page size. */
  20. /* couldn't make __getpagesize hidden, because shm.h uses it in a macro */
  21. extern __typeof(getpagesize) __getpagesize;
  22. int __getpagesize(void)
  23. {
  24. if (__pagesize != 0)
  25. return __pagesize;
  26. #ifdef EXEC_PAGESIZE
  27. return EXEC_PAGESIZE;
  28. #else /* No EXEC_PAGESIZE. */
  29. #ifdef NBPG
  30. #ifndef CLSIZE
  31. #define CLSIZE 1
  32. #endif /* No CLSIZE. */
  33. return NBPG * CLSIZE;
  34. #else /* No NBPG. */
  35. return NBPC;
  36. #endif /* NBPG. */
  37. #endif /* EXEC_PAGESIZE. */
  38. }
  39. /* libc_hidden_proto(getpagesize) */
  40. strong_alias(__getpagesize,getpagesize)
  41. libc_hidden_def(getpagesize)