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
|
// Copyright 2004 Nicholas Miell
//
// This file may be used subject to the terms and conditions of the
// GNU Library General Public License Version 2 as published by the
// Free Software Foundation.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 Library General Public License for more
// details.
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <regex.h>
#include <limits.h>
#include <unistd.h>
#include <errno.h>
#include "proc/version.h"
static void die(const char *msg) NORETURN;
static void die(const char *msg)
{
fputs(msg, stderr);
exit(1);
}
static void version(void) NORETURN;
static void version(void)
{
printf("pwdx (%s)\n", procps_version);
exit(0);
}
int main(int argc, char* argv[])
{
char buf[PATH_MAX+1];
regex_t re;
int i;
if (argc < 2)
die("Usage: pwdx pid...\n");
// Allowed on the command line:
//
// --version
// -V
// /proc/nnnn
// nnnn
//
// where nnnn is any number that doesn't begin with 0.
//
// If --version or -V are present, further arguments are ignored
// completely.
regcomp(&re, "^((/proc/+)?[1-9][0-9]*|-V|--version)$",
REG_EXTENDED|REG_NOSUB);
for (i = 1; i < argc; i++) {
if (regexec(&re, argv[i], 0, NULL, 0) != 0) {
snprintf(buf, sizeof buf, "pwdx: invalid process id: %s\n", argv[i]);
buf[sizeof(buf)-1] = '\0';
die(buf);
}
if (!strcmp("-V", argv[i]) || !strcmp("--version", argv[i]))
version();
}
regfree(&re);
for (i = 1; i < argc; i++) {
char * s = buf;
int len;
// At this point, all arguments are in the form /proc/nnnn
// or nnnn, so a simple check based on the first char is
// possible
if (argv[i][0] != '/')
snprintf(buf, sizeof buf, "/proc/%s/cwd", argv[i]);
else
snprintf(buf, sizeof buf, "%s/cwd", argv[i]);
// buf contains /proc/nnnn/cwd symlink name on entry, the
// target of that symlink on return
if ((len = readlink(buf, buf, PATH_MAX)) < 0) {
s = strerror(errno == ENOENT ? ESRCH : errno);
} else {
buf[len] = 0;
}
printf("%s: %s\n", argv[i], s);
}
return 0;
}
|
