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/* printenv -- print all or part of environment
Copyright (C) 1989, 1991 Free Software Foundation.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* Usage: printenv [variable...]
If no arguments are given, print the entire environment.
If one or more variable names are given, print the value of
each one that is set, and nothing for ones that are not set.
Exit status:
0 if all variables specified were found
1 if not
David MacKenzie and Richard Mlynarik */
#include <stdio.h>
#include <sys/types.h>
#include "system.h"
extern char **environ;
void
main (argc, argv)
int argc;
char **argv;
{
char **env;
char *ep, *ap;
int i;
int matches = 0;
if (argc == 1)
{
for (env = environ; *env; ++env)
puts (*env);
exit (0);
}
for (i = 1; i < argc; ++i)
{
for (env = environ; *env; ++env)
{
ep = *env;
ap = argv[i];
while (*ep != '\0' && *ap != '\0' && *ep++ == *ap++)
if (*ep == '=' && *ap == '\0')
{
puts (ep + 1);
++matches;
break;
}
}
}
exit (matches != argc - 1);
}
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