sysdeps/unix/sysv/linux/sysconf.c

   1 /* Copyright (C) 1991, 1993, 1995 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3
   4 The GNU C Library is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 License, or (at your option) any later version.
   8
   9 The GNU C Library is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <errno.h>
  21 #include <limits.h>
  22 #include <unistd.h>
  23 #include <stddef.h>
  24 #include <stdio.h>
  25 #include <time.h>
  26
  27 extern size_t EXFUN(__getpagesize, (NOARGS));
  28
  29 /* Get the value of the system variable NAME.  */
  30 long int
  31 DEFUN(__sysconf, (name), int name)
  32 {
  33   switch (name)
  34     {
  35     default:
  36       errno = EINVAL;
  37       return -1;
  38
  39     case _SC_ARG_MAX:
  40 #ifdef  ARG_MAX
  41       return ARG_MAX;
  42 #else
  43       return -1;
  44 #endif
  45
  46     case _SC_CHILD_MAX:
  47 #ifdef  CHILD_MAX
  48       return CHILD_MAX;
  49 #else
  50       return -1;
  51 #endif
  52
  53     case _SC_CLK_TCK:
  54 #ifdef  CLK_TCK
  55       return CLK_TCK;
  56 #else
  57       return 60;
  58 #endif
  59
  60     case _SC_NGROUPS_MAX:
  61 #ifdef  NGROUPS_MAX
  62       return NGROUPS_MAX;
  63 #else
  64       return -1;
  65 #endif
  66
  67     case _SC_OPEN_MAX:
  68       return OPEN_MAX;
  69
  70     case _SC_STREAM_MAX:
  71 #ifdef  STREAM_MAX
  72       return STREAM_MAX;
  73 #else
  74       return FOPEN_MAX;
  75 #endif
  76
  77     case _SC_TZNAME_MAX:
  78       return __tzname_max ();
  79
  80     case _SC_JOB_CONTROL:
  81 #ifdef  _POSIX_JOB_CONTROL
  82       return 1;
  83 #else
  84       return -1;
  85 #endif
  86     case _SC_SAVED_IDS:
  87 #ifdef  _POSIX_SAVED_IDS
  88       return 1;
  89 #else
  90       return -1;
  91 #endif
  92     case _SC_VERSION:
  93       return _POSIX_VERSION;
  94
  95     case _SC_PAGESIZE:
  96       return __getpagesize ();
  97
  98     case _SC_BC_BASE_MAX:
  99 #ifdef  BC_BASE_MAX
 100       return BC_BASE_MAX;
 101 #else
 102       return -1;
 103 #endif
 104
 105     case _SC_BC_DIM_MAX:
 106 #ifdef  BC_DIM_MAX
 107       return BC_DIM_MAX;
 108 #else
 109       return -1;
 110 #endif
 111
 112     case _SC_BC_SCALE_MAX:
 113 #ifdef  BC_SCALE_MAX
 114       return BC_SCALE_MAX;
 115 #else
 116       return -1;
 117 #endif
 118
 119     case _SC_BC_STRING_MAX:
 120 #ifdef  BC_STRING_MAX
 121       return BC_STRING_MAX;
 122 #else
 123       return -1;
 124 #endif
 125
 126     case _SC_EQUIV_CLASS_MAX:
 127 #ifdef  EQUIV_CLASS_MAX
 128       return EQUIV_CLASS_MAX;
 129 #else
 130       return -1;
 131 #endif
 132
 133     case _SC_EXPR_NEST_MAX:
 134 #ifdef  EXPR_NEST_MAX
 135       return EXPR_NEST_MAX;
 136 #else
 137       return -1;
 138 #endif
 139
 140     case _SC_LINE_MAX:
 141 #ifdef  LINE_MAX
 142       return LINE_MAX;
 143 #else
 144       return -1;
 145 #endif
 146
 147     case _SC_RE_DUP_MAX:
 148 #ifdef  RE_DUP_MAX
 149       return RE_DUP_MAX;
 150 #else
 151       return -1;
 152 #endif
 153
 154
 155     case _SC_2_VERSION:
 156       /* This is actually supposed to return the version
 157          of the 1003.2 utilities on the system {POSIX2_VERSION}.  */
 158       return _POSIX2_C_VERSION;
 159
 160     case _SC_2_C_BIND:
 161 #ifdef  _POSIX2_C_BIND
 162       return _POSIX2_C_BIND;
 163 #else
 164       return -1;
 165 #endif
 166
 167     case _SC_2_C_DEV:
 168 #ifdef  _POSIX2_C_DEV
 169       return _POSIX2_C_DEV;
 170 #else
 171       return -1;
 172 #endif
 173
 174     case _SC_2_FORT_DEV:
 175 #ifdef  _POSIX2_FORT_DEV
 176       return _POSIX2_FORT_DEV;
 177 #else
 178       return -1;
 179 #endif
 180
 181     case _SC_2_LOCALEDEF:
 182 #ifdef  _POSIX2_LOCALEDEF
 183       return _POSIX2_LOCALEDEF;
 184 #else
 185       return -1;
 186 #endif
 187
 188     case _SC_2_SW_DEV:
 189 #ifdef  _POSIX2_SW_DEV
 190       return _POSIX2_SW_DEV;
 191 #else
 192       return -1;
 193 #endif
 194     }
 195 }
 196
 197 weak_alias (__sysconf, sysconf)