tests/test-environ.c

   1 /* Test of environ variable.
   2    Copyright (C) 2008-2024 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2008.  */
  18
  19 #include <config.h>
  20
  21 #include <unistd.h>
  22
  23 #include <string.h>
  24
  25 int
  26 main ()
  27 {
  28   /* The environment variables that are set even in the weirdest situations
  29      are HOME and PATH.
  30      POSIX says that HOME is initialized by the system, and that PATH may be
  31      unset.  But in practice it's more frequent to see HOME unset and PATH
  32      set.  So we test the presence of PATH.  */
  33   char **remaining_variables = environ;
  34   char *string;
  35
  36   for (; (string = *remaining_variables) != NULL; remaining_variables++)
  37     {
  38       if (strncmp (string, "PATH=", 5) == 0)
  39         /* Found the PATH environment variable.  */
  40         return 0;
  41     }
  42   /* Failed to find the PATH environment variable.  */
  43   return 1;
  44 }