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
|
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1982-2007 AT&T Intellectual Property *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
static const char usage[] =
"[-?\n@(#)$Id: readlink (AT&T Research) 2008-06-08 $\n]"
USAGE_LICENSE
"[+NAME?readlink - read the contents of a symbolic link]"
"[+DESCRIPTION?\breadlink\b returns the contents of the symbolic "
"link referred to by the path argument. Unless the \b-f\b "
"option is specified an error will be returned when the path "
"is not a symbolic link.]"
"[f:canonicalize?The returned value will be an absolute pathname that names "
"the same file, whose resolution does not involve \".\", \"..\", or "
"symbolic links, otherwise only the exact (relative) value will be returned.]"
"[n:no-newline?Supress newline at the end.]"
"[v:verbose?Verbose - print errors.]"
"[+SEE ALSO?\bbasename\b(1),\bdirname\b(2),\breadlink\b(2),\breadpath\n(2)]"
;
#include <cmd.h>
int
b_readlink(int argc, char** argv, void* context)
{
register char* s;
register int i;
register char* m;
register char* x;
int canonicalize = 0,
nonewline = 0,
verbose = 0;
char buf[PATH_MAX+2];
int len = 0;
char *filename,
*resolvedname = NULL;
cmdinit(argc, argv, context, ERROR_CATALOG, 0);
for (;;)
{
switch (optget(argv, usage))
{
case 'f':
canonicalize = opt_info.num;
continue;
case 'n':
nonewline = opt_info.num;
continue;
case 'v':
verbose = opt_info.num;
continue;
case '?':
error(ERROR_usage(2), "%s", opt_info.arg);
continue;
case ':':
error(2, "%s", opt_info.arg);
continue;
}
break;
}
argv += opt_info.index;
argc -= opt_info.index;
if(error_info.errors || argc != 1)
error(ERROR_usage(2),"%s", optusage(NiL));
filename = argv[0];
if (canonicalize)
{
len = resolvepath(filename, buf, sizeof(buf)-2);
}
else
{
len = readlink(filename, buf, sizeof(buf)-2);
}
if (len != -1)
resolvedname = buf;
if (!resolvedname)
{
if (verbose)
error(ERROR_system(1),"%s: readlink failed", filename);
else
return 1;
}
if (!nonewline)
resolvedname[len++] = '\n';
sfwrite(sfstdout, resolvedname, len);
return 0;
}
|
