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
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
/* env - run a program in a modified environment
Copyright (C) 1986-2014 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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */
/* Richard Mlynarik and David MacKenzie */
#include <config.h>
#include <stdio.h>
#include <sys/types.h>
#include <getopt.h>
#include "system.h"
#include "error.h"
#include "quote.h"
/* The official name of this program (e.g., no 'g' prefix). */
#define PROGRAM_NAME "env"
#define AUTHORS \
proper_name ("Richard Mlynarik"), \
proper_name ("David MacKenzie")
static struct option const longopts[] =
{
{"ignore-environment", no_argument, NULL, 'i'},
{"null", no_argument, NULL, '0'},
{"unset", required_argument, NULL, 'u'},
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{NULL, 0, NULL, 0}
};
void
usage (int status)
{
if (status != EXIT_SUCCESS)
emit_try_help ();
else
{
printf (_("\
Usage: %s [OPTION]... [-] [NAME=VALUE]... [COMMAND [ARG]...]\n"),
program_name);
fputs (_("\
Set each NAME to VALUE in the environment and run COMMAND.\n\
"), stdout);
emit_mandatory_arg_note ();
fputs (_("\
-i, --ignore-environment start with an empty environment\n\
-0, --null end each output line with 0 byte rather than newline\n\
-u, --unset=NAME remove variable from the environment\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
fputs (_("\
\n\
A mere - implies -i. If no COMMAND, print the resulting environment.\n\
"), stdout);
emit_ancillary_info ();
}
exit (status);
}
int
main (int argc, char **argv)
{
int optc;
bool ignore_environment = false;
bool opt_nul_terminate_output = false;
initialize_main (&argc, &argv);
set_program_name (argv[0]);
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
initialize_exit_failure (EXIT_CANCELED);
atexit (close_stdout);
while ((optc = getopt_long (argc, argv, "+iu:0", longopts, NULL)) != -1)
{
switch (optc)
{
case 'i':
ignore_environment = true;
break;
case 'u':
break;
case '0':
opt_nul_terminate_output = true;
break;
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
default:
usage (EXIT_CANCELED);
}
}
if (optind < argc && STREQ (argv[optind], "-"))
ignore_environment = true;
if (ignore_environment)
{
static char *dummy_environ[] = { NULL };
environ = dummy_environ;
}
optind = 0; /* Force GNU getopt to re-initialize. */
while ((optc = getopt_long (argc, argv, "+iu:0", longopts, NULL)) != -1)
if (optc == 'u' && unsetenv (optarg))
error (EXIT_CANCELED, errno, _("cannot unset %s"), quote (optarg));
if (optind < argc && STREQ (argv[optind], "-"))
++optind;
char *eq;
while (optind < argc && (eq = strchr (argv[optind], '=')))
{
if (putenv (argv[optind]))
{
*eq = '\0';
error (EXIT_CANCELED, errno, _("cannot set %s"),
quote (argv[optind]));
}
optind++;
}
/* If no program is specified, print the environment and exit. */
if (argc <= optind)
{
char *const *e = environ;
while (*e)
printf ("%s%c", *e++, opt_nul_terminate_output ? '\0' : '\n');
exit (EXIT_SUCCESS);
}
if (opt_nul_terminate_output)
{
error (0, errno, _("cannot specify --null (-0) with command"));
usage (EXIT_CANCELED);
}
execvp (argv[optind], &argv[optind]);
{
int exit_status = (errno == ENOENT ? EXIT_ENOENT : EXIT_CANNOT_INVOKE);
error (0, errno, "%s", argv[optind]);
exit (exit_status);
}
}
|
