Commit | Line | Data |
a0d0e21e |
1 | package Cwd; |
2 | require 5.000; |
3 | require Exporter; |
4633a7c4 |
4 | require Config; |
5 | |
6 | # Use osname for portability switches (doubled to cheaply avoid -w warning) |
7 | my $osname = $Config::Config{'osname'} || $Config::Config{'osname'}; |
8 | |
a0d0e21e |
9 | |
f06db76b |
10 | =head1 NAME |
11 | |
12 | getcwd - get pathname of current working directory |
13 | |
14 | =head1 SYNOPSIS |
15 | |
4633a7c4 |
16 | use Cwd; |
17 | $dir = cwd; |
18 | |
19 | use Cwd; |
20 | $dir = getcwd; |
f06db76b |
21 | |
22 | use Cwd; |
4633a7c4 |
23 | $dir = fastgetcwd; |
f06db76b |
24 | |
25 | use Cwd 'chdir'; |
26 | chdir "/tmp"; |
27 | print $ENV{'PWD'}; |
28 | |
29 | =head1 DESCRIPTION |
30 | |
31 | The getcwd() function re-implements the getcwd(3) (or getwd(3)) functions |
4633a7c4 |
32 | in Perl. |
f06db76b |
33 | |
cb1a09d0 |
34 | The fastcwd() function looks the same as getcwd(), but runs faster. |
f06db76b |
35 | It's also more dangerous because you might conceivably chdir() out of a |
36 | directory that you can't chdir() back into. |
37 | |
4633a7c4 |
38 | The cwd() function looks the same as getcwd and fastgetcwd but is |
39 | implemented using the most natural and safe form for the current |
40 | architecture. For most systems it is identical to `pwd` (but without |
41 | the trailing line terminator). It is recommended that cwd (or another |
42 | *cwd() function) is used in I<all> code to ensure portability. |
43 | |
44 | If you ask to override your chdir() built-in function, then your PWD |
45 | environment variable will be kept up to date. (See |
46 | L<perlsub/Overriding builtin functions>.) Note that it will only be |
47 | kept up to date it all packages which use chdir import it from Cwd. |
48 | |
f06db76b |
49 | =cut |
50 | |
a0d0e21e |
51 | @ISA = qw(Exporter); |
4633a7c4 |
52 | @EXPORT = qw(cwd getcwd fastcwd); |
a0d0e21e |
53 | @EXPORT_OK = qw(chdir); |
54 | |
4633a7c4 |
55 | # use strict; |
56 | |
57 | sub _backtick_pwd { # The 'natural and safe form' for UNIX (pwd may be setuid root) |
58 | my $cwd; |
59 | chop($cwd = `pwd`); |
60 | $cwd; |
61 | } |
62 | |
63 | # Since some ports may predefine cwd internally (e.g., NT) |
64 | # we take care not to override an existing definition for cwd(). |
65 | |
66 | *cwd = \&_backtick_pwd unless defined &cwd; |
a0d0e21e |
67 | |
748a9306 |
68 | |
a0d0e21e |
69 | # By Brandon S. Allbery |
70 | # |
71 | # Usage: $cwd = getcwd(); |
72 | |
73 | sub getcwd |
74 | { |
75 | my($dotdots, $cwd, @pst, @cst, $dir, @tst); |
76 | |
77 | unless (@cst = stat('.')) |
78 | { |
79 | warn "stat(.): $!"; |
80 | return ''; |
81 | } |
82 | $cwd = ''; |
42793c05 |
83 | $dotdots = ''; |
a0d0e21e |
84 | do |
85 | { |
86 | $dotdots .= '/' if $dotdots; |
87 | $dotdots .= '..'; |
88 | @pst = @cst; |
89 | unless (opendir(PARENT, $dotdots)) |
90 | { |
91 | warn "opendir($dotdots): $!"; |
92 | return ''; |
93 | } |
94 | unless (@cst = stat($dotdots)) |
95 | { |
96 | warn "stat($dotdots): $!"; |
97 | closedir(PARENT); |
98 | return ''; |
99 | } |
100 | if ($pst[0] == $cst[0] && $pst[1] == $cst[1]) |
101 | { |
102 | $dir = ''; |
103 | } |
104 | else |
105 | { |
106 | do |
107 | { |
3edbfbe5 |
108 | unless (defined ($dir = readdir(PARENT))) |
109 | { |
a0d0e21e |
110 | warn "readdir($dotdots): $!"; |
111 | closedir(PARENT); |
112 | return ''; |
113 | } |
114 | unless (@tst = lstat("$dotdots/$dir")) |
115 | { |
116 | warn "lstat($dotdots/$dir): $!"; |
37120919 |
117 | # Just because you can't lstat this directory |
118 | # doesn't mean you'll never find the right one. |
119 | # closedir(PARENT); |
120 | # return ''; |
a0d0e21e |
121 | } |
122 | } |
123 | while ($dir eq '.' || $dir eq '..' || $tst[0] != $pst[0] || |
124 | $tst[1] != $pst[1]); |
125 | } |
126 | $cwd = "$dir/$cwd"; |
127 | closedir(PARENT); |
128 | } while ($dir); |
3edbfbe5 |
129 | chop($cwd); # drop the trailing / |
a0d0e21e |
130 | $cwd; |
131 | } |
132 | |
133 | |
134 | |
135 | # By John Bazik |
136 | # |
137 | # Usage: $cwd = &fastcwd; |
138 | # |
139 | # This is a faster version of getcwd. It's also more dangerous because |
140 | # you might chdir out of a directory that you can't chdir back into. |
141 | |
142 | sub fastcwd { |
143 | my($odev, $oino, $cdev, $cino, $tdev, $tino); |
144 | my(@path, $path); |
145 | local(*DIR); |
146 | |
147 | ($cdev, $cino) = stat('.'); |
148 | for (;;) { |
40000a8c |
149 | my $direntry; |
a0d0e21e |
150 | ($odev, $oino) = ($cdev, $cino); |
151 | chdir('..'); |
152 | ($cdev, $cino) = stat('.'); |
153 | last if $odev == $cdev && $oino == $cino; |
154 | opendir(DIR, '.'); |
155 | for (;;) { |
40000a8c |
156 | $direntry = readdir(DIR); |
157 | next if $direntry eq '.'; |
158 | next if $direntry eq '..'; |
a0d0e21e |
159 | |
40000a8c |
160 | last unless defined $direntry; |
161 | ($tdev, $tino) = lstat($direntry); |
a0d0e21e |
162 | last unless $tdev != $odev || $tino != $oino; |
163 | } |
164 | closedir(DIR); |
40000a8c |
165 | unshift(@path, $direntry); |
a0d0e21e |
166 | } |
167 | chdir($path = '/' . join('/', @path)); |
168 | $path; |
169 | } |
170 | |
171 | |
4633a7c4 |
172 | # Keeps track of current working directory in PWD environment var |
a0d0e21e |
173 | # Usage: |
174 | # use Cwd 'chdir'; |
175 | # chdir $newdir; |
176 | |
4633a7c4 |
177 | my $chdir_init = 0; |
a0d0e21e |
178 | |
4633a7c4 |
179 | sub chdir_init { |
180 | if ($ENV{'PWD'} and $osname ne 'os2') { |
a0d0e21e |
181 | my($dd,$di) = stat('.'); |
182 | my($pd,$pi) = stat($ENV{'PWD'}); |
183 | if (!defined $dd or !defined $pd or $di != $pi or $dd != $pd) { |
4633a7c4 |
184 | $ENV{'PWD'} = cwd(); |
a0d0e21e |
185 | } |
186 | } |
187 | else { |
4633a7c4 |
188 | $ENV{'PWD'} = cwd(); |
a0d0e21e |
189 | } |
4633a7c4 |
190 | # Strip an automounter prefix (where /tmp_mnt/foo/bar == /foo/bar) |
a0d0e21e |
191 | if ($ENV{'PWD'} =~ m|(/[^/]+(/[^/]+/[^/]+))(.*)|) { |
192 | my($pd,$pi) = stat($2); |
193 | my($dd,$di) = stat($1); |
194 | if (defined $pd and defined $dd and $di == $pi and $dd == $pd) { |
195 | $ENV{'PWD'}="$2$3"; |
196 | } |
197 | } |
198 | $chdir_init = 1; |
199 | } |
200 | |
201 | sub chdir { |
4633a7c4 |
202 | my $newdir = shift || ''; # allow for no arg (chdir to HOME dir) |
203 | $newdir =~ s|///*|/|g; |
a0d0e21e |
204 | chdir_init() unless $chdir_init; |
4633a7c4 |
205 | return 0 unless CORE::chdir $newdir; |
206 | if ($osname eq 'VMS') { return $ENV{'PWD'} = $ENV{'DEFAULT'} } |
748a9306 |
207 | |
a0d0e21e |
208 | if ($newdir =~ m#^/#) { |
209 | $ENV{'PWD'} = $newdir; |
4633a7c4 |
210 | } else { |
211 | my @curdir = split(m#/#,$ENV{'PWD'}); |
212 | @curdir = ('') unless @curdir; |
213 | my $component; |
a0d0e21e |
214 | foreach $component (split(m#/#, $newdir)) { |
215 | next if $component eq '.'; |
216 | pop(@curdir),next if $component eq '..'; |
217 | push(@curdir,$component); |
218 | } |
219 | $ENV{'PWD'} = join('/',@curdir) || '/'; |
220 | } |
4633a7c4 |
221 | 1; |
a0d0e21e |
222 | } |
223 | |
4633a7c4 |
224 | |
225 | # --- PORTING SECTION --- |
226 | |
227 | # VMS: $ENV{'DEFAULT'} points to default directory at all times |
228 | # 08-Dec-1994 Charles Bailey bailey@genetics.upenn.edu |
229 | # Note: Use of Cwd::getcwd() or Cwd::chdir() (but not Cwd::fastcwd()) |
230 | # causes the logical name PWD to be defined in the process |
231 | # logical name table as the default device and directory |
232 | # seen by Perl. This may not be the same as the default device |
233 | # and directory seen by DCL after Perl exits, since the effects |
234 | # the CRTL chdir() function persist only until Perl exits. |
235 | # This does not apply to other systems (where only chdir() sets PWD). |
236 | |
237 | sub _vms_cwd { |
238 | return $ENV{'DEFAULT'} |
239 | } |
240 | sub _vms_pwd { |
241 | return $ENV{'PWD'} = $ENV{'DEFAULT'} |
242 | } |
243 | sub _os2_cwd { |
244 | $ENV{'PWD'} = `cmd /c cd`; |
245 | chop $ENV{'PWD'}; |
246 | $ENV{'PWD'} =~ s:\\:/:g ; |
247 | return $ENV{'PWD'}; |
248 | } |
249 | |
250 | if ($osname eq 'VMS') { |
251 | |
252 | *cwd = \&_vms_pwd; |
253 | *getcwd = \&_vms_pwd; |
254 | *fastgetcwd = \&_vms_cwd; |
255 | } |
256 | elsif ($osname eq 'NT') { |
257 | |
258 | *getcwd = \&cwd; |
259 | *fastgetcwd = \&cwd; |
260 | } |
261 | elsif ($osname eq 'os2') { |
262 | *cwd = \&_os2_cwd; |
263 | *getcwd = \&_os2_cwd; |
264 | *fastgetcwd = \&_os2_cwd; |
265 | *fastcwd = \&_os2_cwd; |
266 | } |
267 | |
268 | # package main; eval join('',<DATA>) || die $@; # quick test |
269 | |
a0d0e21e |
270 | 1; |
271 | |
4633a7c4 |
272 | __END__ |
273 | BEGIN { import Cwd qw(:DEFAULT chdir); } |
274 | print join("\n", cwd, getcwd, fastcwd, ""); |
275 | chdir('..'); |
276 | print join("\n", cwd, getcwd, fastcwd, ""); |
277 | print "$ENV{PWD}\n"; |