LXR busybox/shell/ash_test/printenv.c

   1/* printenv -- minimal clone of BSD printenv(1).
   2
   3   usage: printenv [varname]
   4
   5   Chet Ramey
   6   chet@po.cwru.edu
   7*/
   8
   9/* Copyright (C) 1997-2002 Free Software Foundation, Inc.
  10
  11   This file is part of GNU Bash, the Bourne Again SHell.
  12
  13   Bash is free software; you can redistribute it and/or modify it under
  14   the terms of the GNU General Public License as published by the Free
  15   Software Foundation; either version 2, or (at your option) any later
  16   version.
  17
  18   Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  19   WARRANTY; without even the implied warranty of MERCHANTABILITY or
  20   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  21   for more details.
  22
  23   You should have received a copy of the GNU General Public License along
  24   with Bash; see the file COPYING.  If not, write to the Free Software
  25   Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
  26
  27#include <stdio.h>
  28#include <stdlib.h>
  29#include <string.h>
  30
  31extern char **environ;
  32
  33int
  34main (argc, argv)
  35     int argc;
  36     char **argv;
  37{
  38  register char **envp, *eval;
  39  int len;
  40
  41  argv++;
  42  argc--;
  43
  44  /* printenv */
  45  if (argc == 0)
  46    {
  47      for (envp = environ; *envp; envp++)
  48        puts (*envp);
  49      exit(EXIT_SUCCESS);
  50    }
  51
  52  /* printenv varname */
  53  len = strlen (*argv);
  54  for (envp = environ; *envp; envp++)
  55    {
  56      if (**argv == **envp && strncmp (*envp, *argv, len) == 0)
  57        {
  58          eval = *envp + len;
  59          /* If the environment variable doesn't have an `=', ignore it. */
  60          if (*eval == '=')
  61            {
  62              puts (eval + 1);
  63              exit(EXIT_SUCCESS);
  64            }
  65        }
  66    }
  67  exit(EXIT_FAILURE);
  68}
  69