src/getpagesize.h

   1 /* Emulate getpagesize on systems that lack it.
   2    Copyright (C) 1986, 1992, 1995, 2001 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef HAVE_GETPAGESIZE
  22
  23 # ifdef VMS
  24 #  define getpagesize() 512
  25 # endif
  26
  27 # ifdef HAVE_UNISTD_H
  28 #  include <unistd.h>
  29 # endif
  30
  31 # ifdef _SC_PAGESIZE
  32 #  define getpagesize() sysconf(_SC_PAGESIZE)
  33 # else /* no _SC_PAGESIZE */
  34 #  ifdef HAVE_SYS_PARAM_H
  35 #   include <sys/param.h>
  36 #   ifdef EXEC_PAGESIZE
  37 #    define getpagesize() EXEC_PAGESIZE
  38 #   else /* no EXEC_PAGESIZE */
  39 #    ifdef NBPG
  40 #     define getpagesize() NBPG * CLSIZE
  41 #     ifndef CLSIZE
  42 #      define CLSIZE 1
  43 #     endif /* no CLSIZE */
  44 #    else /* no NBPG */
  45 #     ifdef NBPC
  46 #      define getpagesize() NBPC
  47 #     else /* no NBPC */
  48 #      ifdef PAGESIZE
  49 #       define getpagesize() PAGESIZE
  50 #      endif /* PAGESIZE */
  51 #     endif /* no NBPC */
  52 #    endif /* no NBPG */
  53 #   endif /* no EXEC_PAGESIZE */
  54 #  else /* no HAVE_SYS_PARAM_H */
  55 #   define getpagesize() 8192   /* punt totally */
  56 #  endif /* no HAVE_SYS_PARAM_H */
  57 # endif /* no _SC_PAGESIZE */
  58
  59 #endif /* no HAVE_GETPAGESIZE */