1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
|
/* printenv -- print all or part of environment
Copyright (C) 89, 90, 91, 92, 93, 94, 1995 Free Software Foundation, Inc.
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 <config.h>
#include <stdio.h>
#include <sys/types.h>
#include <getopt.h>
#include "version.h"
#include "system.h"
#include "error.h"
/* The name this program was run with. */
char *program_name;
/* If nonzero, display usage information and exit. */
static int show_help;
/* If nonzero, print the version on standard output and exit. */
static int show_version;
static struct option const long_options[] =
{
{"help", no_argument, &show_help, 1},
{"version", no_argument, &show_version, 1},
{0, 0, 0, 0}
};
extern char **environ;
static void
usage (int status)
{
if (status != 0)
fprintf (stderr, _("Try `%s --help' for more information.\n"),
program_name);
else
{
printf (_("Usage: %s [OPTION]... [VARIABLE]...\n"), program_name);
printf (_("\
If no environment VARIABLE specified, print them all.\n\
\n\
--help display this help and exit\n\
--version output version information and exit\n"));
}
exit (status);
}
void
main (int argc, char **argv)
{
char **env;
char *ep, *ap;
int i;
int matches = 0;
int c;
int exit_status;
program_name = argv[0];
while ((c = getopt_long (argc, argv, "", long_options, (int *) 0)) != EOF)
{
switch (c)
{
case 0:
break;
default:
usage (1);
}
}
if (show_version)
{
printf ("printenv - %s\n", version_string);
exit (0);
}
if (show_help)
usage (0);
if (optind == argc)
{
for (env = environ; *env != NULL; ++env)
puts (*env);
exit_status = 0;
}
else
{
for (i = optind; 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_status = (matches != argc - optind);
}
if (ferror (stdout) || fclose (stdout) == EOF)
error (2, errno, _("standard output"));
exit (exit_status);
}
|
