lib/posixver.c

   1 /* Which POSIX version to conform to, for utilities.
   2
   3    Copyright (C) 2002 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify it
   6    under the terms of the GNU Library General Public License as published
   7    by the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with this program; if not, write to the Free Software
  17    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  18    USA.  */
  19
  20 /* Written by Paul Eggert.  */
  21
  22 #if HAVE_CONFIG_H
  23 # include <config.h>
  24 #endif
  25
  26 #include <limits.h>
  27
  28 #include <stdlib.h>
  29 #if !HAVE_DECL_GETENV && !defined getenv
  30 char *getenv ();
  31 #endif
  32
  33 #if HAVE_UNISTD_H
  34 # include <unistd.h>
  35 #endif
  36 #ifndef _POSIX2_VERSION
  37 # define _POSIX2_VERSION 0
  38 #endif
  39
  40 /* The POSIX version that utilities should conform to.  The default is
  41    specified by the system.  */
  42
  43 int
  44 posix2_version (void)
  45 {
  46   long int v = _POSIX2_VERSION;
  47   char const *s = getenv ("_POSIX2_VERSION");
  48
  49   if (s && *s)
  50     {
  51       char *e;
  52       long int i = strtol (s, &e, 10);
  53       if (! *e)
  54         v = i;
  55     }
  56
  57   return v < INT_MIN ? INT_MIN : v < INT_MAX ? v : INT_MAX;
  58 }