Commit | Line | Data |
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a0d0e21e | 1 | package Cwd; |
4d6b4052 | 2 | require 5.6.0; |
a0d0e21e | 3 | |
f06db76b AD |
4 | =head1 NAME |
5 | ||
902bacac | 6 | Cwd - get pathname of current working directory |
f06db76b AD |
7 | |
8 | =head1 SYNOPSIS | |
9 | ||
4633a7c4 | 10 | use Cwd; |
04929354 | 11 | my $dir = getcwd; |
4633a7c4 | 12 | |
04929354 MS |
13 | use Cwd 'abs_path'; |
14 | my $abs_path = abs_path($file); | |
f06db76b | 15 | |
04929354 | 16 | =head1 DESCRIPTION |
902bacac | 17 | |
04929354 MS |
18 | This module provides functions for determining the pathname of the |
19 | current working directory. It is recommended that getcwd (or another | |
20 | *cwd() function) be used in I<all> code to ensure portability. | |
f06db76b | 21 | |
04929354 MS |
22 | By default, it exports the functions cwd(), getcwd(), fastcwd(), and |
23 | fastgetcwd() into the caller's namespace. | |
f06db76b | 24 | |
20408e3c | 25 | |
04929354 | 26 | =head2 getcwd and friends |
20408e3c | 27 | |
04929354 MS |
28 | Each of these functions are called without arguments and return the |
29 | absolute path of the current working directory. | |
f06db76b | 30 | |
04929354 MS |
31 | =over 4 |
32 | ||
33 | =item getcwd | |
34 | ||
35 | my $cwd = getcwd(); | |
36 | ||
37 | Returns the current working directory. | |
38 | ||
39 | Re-implements the getcwd(3) (or getwd(3)) functions in Perl. | |
40 | ||
41 | =item cwd | |
42 | ||
43 | my $cwd = cwd(); | |
44 | ||
45 | The cwd() is the most natural form for the current architecture. For | |
46 | most systems it is identical to `pwd` (but without the trailing line | |
47 | terminator). | |
48 | ||
49 | Unfortunately, cwd() tends to break if called under taint mode. | |
50 | ||
51 | =item fastcwd | |
52 | ||
53 | my $cwd = fastcwd(); | |
54 | ||
55 | A more dangerous version of getcwd(), but potentially faster. | |
56 | ||
57 | It might conceivably chdir() you out of a directory that it can't | |
58 | chdir() you back into. If fastcwd encounters a problem it will return | |
59 | undef but will probably leave you in a different directory. For a | |
60 | measure of extra security, if everything appears to have worked, the | |
61 | fastcwd() function will check that it leaves you in the same directory | |
62 | that it started in. If it has changed it will C<die> with the message | |
63 | "Unstable directory path, current directory changed | |
64 | unexpectedly". That should never happen. | |
65 | ||
66 | =item fastgetcwd | |
67 | ||
68 | my $cwd = fastgetcwd(); | |
f06db76b | 69 | |
902bacac | 70 | The fastgetcwd() function is provided as a synonym for cwd(). |
fb73857a | 71 | |
04929354 MS |
72 | =back |
73 | ||
902bacac | 74 | |
04929354 MS |
75 | =head2 abs_path and friends |
76 | ||
77 | These functions are exported only on request. They each take a single | |
78 | argument and return the absolute pathname for it. | |
79 | ||
80 | =over 4 | |
81 | ||
82 | =item abs_path | |
83 | ||
84 | my $abs_path = abs_path($file); | |
85 | ||
86 | Uses the same algorithm as getcwd(). Symbolic links and relative-path | |
87 | components ("." and "..") are resolved to return the canonical | |
88 | pathname, just like realpath(3). | |
89 | ||
90 | =item realpath | |
91 | ||
92 | my $abs_path = realpath($file); | |
93 | ||
94 | A synonym for abs_path(). | |
95 | ||
96 | =item fast_abs_path | |
97 | ||
98 | my $abs_path = abs_path($file); | |
99 | ||
100 | A more dangerous, but potentially faster version of abs_path. | |
101 | ||
102 | =back | |
103 | ||
104 | =head2 $ENV{PWD} | |
105 | ||
106 | If you ask to override your chdir() built-in function, | |
107 | ||
108 | use Cwd qw(chdir); | |
109 | ||
110 | then your PWD environment variable will be kept up to date. Note that | |
111 | it will only be kept up to date if all packages which use chdir import | |
112 | it from Cwd. | |
4633a7c4 | 113 | |
4633a7c4 | 114 | |
4d6b4052 JH |
115 | =head1 NOTES |
116 | ||
117 | =over 4 | |
118 | ||
119 | =item * | |
120 | ||
04929354 MS |
121 | Since the path seperators are different on some operating systems ('/' |
122 | on Unix, ':' on MacPerl, etc...) we recommend you use the File::Spec | |
123 | modules wherever portability is a concern. | |
124 | ||
04929354 | 125 | =item * |
4d6b4052 JH |
126 | |
127 | Actually, on Mac OS, the C<getcwd()>, C<fastgetcwd()> and C<fastcwd()> | |
128 | functions are all aliases for the C<cwd()> function, which, on Mac OS, | |
129 | calls `pwd`. Likewise, the C<abs_path()> function is an alias for | |
130 | C<fast_abs_path()>. | |
131 | ||
132 | =back | |
133 | ||
04929354 MS |
134 | =head1 SEE ALSO |
135 | ||
136 | L<File::chdir> | |
137 | ||
f06db76b AD |
138 | =cut |
139 | ||
b060a406 | 140 | use strict; |
96e4d5b1 | 141 | |
142 | use Carp; | |
143 | ||
04929354 | 144 | our $VERSION = '2.06'; |
96e4d5b1 | 145 | |
b060a406 TJ |
146 | use base qw/ Exporter /; |
147 | our @EXPORT = qw(cwd getcwd fastcwd fastgetcwd); | |
148 | our @EXPORT_OK = qw(chdir abs_path fast_abs_path realpath fast_realpath); | |
a0d0e21e | 149 | |
f5f423e4 IZ |
150 | # sys_cwd may keep the builtin command |
151 | ||
152 | # All the functionality of this module may provided by builtins, | |
153 | # there is no sense to process the rest of the file. | |
154 | # The best choice may be to have this in BEGIN, but how to return from BEGIN? | |
155 | ||
156 | if ($^O eq 'os2' && defined &sys_cwd && defined &sys_abspath) { | |
157 | local $^W = 0; | |
158 | *cwd = \&sys_cwd; | |
159 | *getcwd = \&cwd; | |
160 | *fastgetcwd = \&cwd; | |
161 | *fastcwd = \&cwd; | |
162 | *abs_path = \&sys_abspath; | |
163 | *fast_abs_path = \&abs_path; | |
164 | *realpath = \&abs_path; | |
165 | *fast_realpath = \&abs_path; | |
166 | return 1; | |
167 | } | |
168 | ||
f22d8e4b DM |
169 | eval { |
170 | require XSLoader; | |
171 | XSLoader::load('Cwd'); | |
172 | }; | |
4633a7c4 | 173 | |
96e4d5b1 | 174 | |
3547aa9a MS |
175 | # Find the pwd command in the expected locations. We assume these |
176 | # are safe. This prevents _backtick_pwd() consulting $ENV{PATH} | |
177 | # so everything works under taint mode. | |
178 | my $pwd_cmd; | |
179 | foreach my $try (qw(/bin/pwd /usr/bin/pwd)) { | |
180 | if( -x $try ) { | |
181 | $pwd_cmd = $try; | |
182 | last; | |
183 | } | |
184 | } | |
185 | $pwd_cmd ||= 'pwd'; | |
186 | ||
187 | # The 'natural and safe form' for UNIX (pwd may be setuid root) | |
8b88ae92 | 188 | sub _backtick_pwd { |
3547aa9a | 189 | my $cwd = `$pwd_cmd`; |
7e03f963 TJ |
190 | # `pwd` may fail e.g. if the disk is full |
191 | chomp($cwd) if defined $cwd; | |
4633a7c4 | 192 | $cwd; |
8b88ae92 | 193 | } |
4633a7c4 LW |
194 | |
195 | # Since some ports may predefine cwd internally (e.g., NT) | |
196 | # we take care not to override an existing definition for cwd(). | |
197 | ||
ea54c8bd EC |
198 | unless(defined &cwd) { |
199 | # The pwd command is not available in some chroot(2)'ed environments | |
4aecb5b5 | 200 | if($^O eq 'MacOS' || grep { -x "$_/pwd" } split(':', $ENV{PATH})) { |
ea54c8bd EC |
201 | *cwd = \&_backtick_pwd; |
202 | } | |
203 | else { | |
204 | *cwd = \&getcwd; | |
205 | } | |
206 | } | |
a0d0e21e | 207 | |
1f4f94f5 RS |
208 | # set a reasonable (and very safe) default for fastgetcwd, in case it |
209 | # isn't redefined later (20001212 rspier) | |
210 | *fastgetcwd = \&cwd; | |
748a9306 | 211 | |
a0d0e21e LW |
212 | # By Brandon S. Allbery |
213 | # | |
214 | # Usage: $cwd = getcwd(); | |
215 | ||
216 | sub getcwd | |
217 | { | |
07569ed3 | 218 | abs_path('.'); |
a0d0e21e LW |
219 | } |
220 | ||
4633a7c4 | 221 | # Keeps track of current working directory in PWD environment var |
a0d0e21e LW |
222 | # Usage: |
223 | # use Cwd 'chdir'; | |
224 | # chdir $newdir; | |
225 | ||
4633a7c4 | 226 | my $chdir_init = 0; |
a0d0e21e | 227 | |
4633a7c4 | 228 | sub chdir_init { |
3b8e3443 | 229 | if ($ENV{'PWD'} and $^O ne 'os2' and $^O ne 'dos' and $^O ne 'MSWin32') { |
a0d0e21e LW |
230 | my($dd,$di) = stat('.'); |
231 | my($pd,$pi) = stat($ENV{'PWD'}); | |
232 | if (!defined $dd or !defined $pd or $di != $pi or $dd != $pd) { | |
4633a7c4 | 233 | $ENV{'PWD'} = cwd(); |
a0d0e21e LW |
234 | } |
235 | } | |
236 | else { | |
3b8e3443 GS |
237 | my $wd = cwd(); |
238 | $wd = Win32::GetFullPathName($wd) if $^O eq 'MSWin32'; | |
239 | $ENV{'PWD'} = $wd; | |
a0d0e21e | 240 | } |
4633a7c4 | 241 | # Strip an automounter prefix (where /tmp_mnt/foo/bar == /foo/bar) |
3b8e3443 | 242 | if ($^O ne 'MSWin32' and $ENV{'PWD'} =~ m|(/[^/]+(/[^/]+/[^/]+))(.*)|s) { |
a0d0e21e LW |
243 | my($pd,$pi) = stat($2); |
244 | my($dd,$di) = stat($1); | |
245 | if (defined $pd and defined $dd and $di == $pi and $dd == $pd) { | |
246 | $ENV{'PWD'}="$2$3"; | |
247 | } | |
248 | } | |
249 | $chdir_init = 1; | |
250 | } | |
251 | ||
252 | sub chdir { | |
22978713 | 253 | my $newdir = @_ ? shift : ''; # allow for no arg (chdir to HOME dir) |
3b8e3443 | 254 | $newdir =~ s|///*|/|g unless $^O eq 'MSWin32'; |
a0d0e21e | 255 | chdir_init() unless $chdir_init; |
4ffa1610 JH |
256 | my $newpwd; |
257 | if ($^O eq 'MSWin32') { | |
258 | # get the full path name *before* the chdir() | |
259 | $newpwd = Win32::GetFullPathName($newdir); | |
260 | } | |
261 | ||
4633a7c4 | 262 | return 0 unless CORE::chdir $newdir; |
4ffa1610 | 263 | |
3b8e3443 GS |
264 | if ($^O eq 'VMS') { |
265 | return $ENV{'PWD'} = $ENV{'DEFAULT'} | |
266 | } | |
4aecb5b5 JH |
267 | elsif ($^O eq 'MacOS') { |
268 | return $ENV{'PWD'} = cwd(); | |
269 | } | |
3b8e3443 | 270 | elsif ($^O eq 'MSWin32') { |
4ffa1610 | 271 | $ENV{'PWD'} = $newpwd; |
3b8e3443 GS |
272 | return 1; |
273 | } | |
748a9306 | 274 | |
392d8ab8 | 275 | if ($newdir =~ m#^/#s) { |
a0d0e21e | 276 | $ENV{'PWD'} = $newdir; |
4633a7c4 LW |
277 | } else { |
278 | my @curdir = split(m#/#,$ENV{'PWD'}); | |
279 | @curdir = ('') unless @curdir; | |
280 | my $component; | |
a0d0e21e LW |
281 | foreach $component (split(m#/#, $newdir)) { |
282 | next if $component eq '.'; | |
283 | pop(@curdir),next if $component eq '..'; | |
284 | push(@curdir,$component); | |
285 | } | |
286 | $ENV{'PWD'} = join('/',@curdir) || '/'; | |
287 | } | |
4633a7c4 | 288 | 1; |
a0d0e21e LW |
289 | } |
290 | ||
e4c51978 GS |
291 | # added function alias for those of us more |
292 | # used to the libc function. --tchrist 27-Jan-00 | |
293 | *realpath = \&abs_path; | |
294 | ||
96e4d5b1 | 295 | sub fast_abs_path { |
296 | my $cwd = getcwd(); | |
4d6b4052 JH |
297 | require File::Spec; |
298 | my $path = @_ ? shift : File::Spec->curdir; | |
e79e61e4 | 299 | CORE::chdir($path) || croak "Cannot chdir to $path:$!"; |
96e4d5b1 | 300 | my $realpath = getcwd(); |
e79e61e4 | 301 | CORE::chdir($cwd) || croak "Cannot chdir back to $cwd:$!"; |
96e4d5b1 | 302 | $realpath; |
8b88ae92 NIS |
303 | } |
304 | ||
e4c51978 GS |
305 | # added function alias to follow principle of least surprise |
306 | # based on previous aliasing. --tchrist 27-Jan-00 | |
307 | *fast_realpath = \&fast_abs_path; | |
308 | ||
4633a7c4 LW |
309 | |
310 | # --- PORTING SECTION --- | |
311 | ||
312 | # VMS: $ENV{'DEFAULT'} points to default directory at all times | |
bd3fa61c | 313 | # 06-Mar-1996 Charles Bailey bailey@newman.upenn.edu |
c6538b72 | 314 | # Note: Use of Cwd::chdir() causes the logical name PWD to be defined |
8b88ae92 NIS |
315 | # in the process logical name table as the default device and directory |
316 | # seen by Perl. This may not be the same as the default device | |
4633a7c4 LW |
317 | # and directory seen by DCL after Perl exits, since the effects |
318 | # the CRTL chdir() function persist only until Perl exits. | |
4633a7c4 LW |
319 | |
320 | sub _vms_cwd { | |
96e4d5b1 | 321 | return $ENV{'DEFAULT'}; |
322 | } | |
323 | ||
324 | sub _vms_abs_path { | |
325 | return $ENV{'DEFAULT'} unless @_; | |
326 | my $path = VMS::Filespec::pathify($_[0]); | |
327 | croak("Invalid path name $_[0]") unless defined $path; | |
328 | return VMS::Filespec::rmsexpand($path); | |
4633a7c4 | 329 | } |
68dc0745 | 330 | |
4633a7c4 LW |
331 | sub _os2_cwd { |
332 | $ENV{'PWD'} = `cmd /c cd`; | |
333 | chop $ENV{'PWD'}; | |
334 | $ENV{'PWD'} =~ s:\\:/:g ; | |
335 | return $ENV{'PWD'}; | |
336 | } | |
337 | ||
96e4d5b1 | 338 | sub _win32_cwd { |
2d7a9237 | 339 | $ENV{'PWD'} = Win32::GetCwd(); |
96e4d5b1 | 340 | $ENV{'PWD'} =~ s:\\:/:g ; |
341 | return $ENV{'PWD'}; | |
342 | } | |
343 | ||
344 | *_NT_cwd = \&_win32_cwd if (!defined &_NT_cwd && | |
2d7a9237 | 345 | defined &Win32::GetCwd); |
96e4d5b1 | 346 | |
347 | *_NT_cwd = \&_os2_cwd unless defined &_NT_cwd; | |
68dc0745 | 348 | |
39e571d4 LM |
349 | sub _dos_cwd { |
350 | if (!defined &Dos::GetCwd) { | |
351 | $ENV{'PWD'} = `command /c cd`; | |
352 | chop $ENV{'PWD'}; | |
353 | $ENV{'PWD'} =~ s:\\:/:g ; | |
354 | } else { | |
355 | $ENV{'PWD'} = Dos::GetCwd(); | |
356 | } | |
55497cff | 357 | return $ENV{'PWD'}; |
358 | } | |
359 | ||
7fbf1995 NA |
360 | sub _qnx_cwd { |
361 | $ENV{'PWD'} = `/usr/bin/fullpath -t`; | |
362 | chop $ENV{'PWD'}; | |
363 | return $ENV{'PWD'}; | |
364 | } | |
365 | ||
366 | sub _qnx_abs_path { | |
fa921dc6 | 367 | my $path = @_ ? shift : '.'; |
7fbf1995 NA |
368 | my $realpath=`/usr/bin/fullpath -t $path`; |
369 | chop $realpath; | |
370 | return $realpath; | |
371 | } | |
372 | ||
ed79a026 OF |
373 | sub _epoc_cwd { |
374 | $ENV{'PWD'} = EPOC::getcwd(); | |
375 | return $ENV{'PWD'}; | |
376 | } | |
377 | ||
ac1ad7f0 | 378 | { |
db376a24 | 379 | no warnings; # assignments trigger 'subroutine redefined' warning |
4633a7c4 | 380 | |
ac1ad7f0 | 381 | if ($^O eq 'VMS') { |
96e4d5b1 | 382 | *cwd = \&_vms_cwd; |
383 | *getcwd = \&_vms_cwd; | |
384 | *fastcwd = \&_vms_cwd; | |
385 | *fastgetcwd = \&_vms_cwd; | |
386 | *abs_path = \&_vms_abs_path; | |
387 | *fast_abs_path = \&_vms_abs_path; | |
ac1ad7f0 PM |
388 | } |
389 | elsif ($^O eq 'NT' or $^O eq 'MSWin32') { | |
390 | # We assume that &_NT_cwd is defined as an XSUB or in the core. | |
96e4d5b1 | 391 | *cwd = \&_NT_cwd; |
392 | *getcwd = \&_NT_cwd; | |
393 | *fastcwd = \&_NT_cwd; | |
394 | *fastgetcwd = \&_NT_cwd; | |
395 | *abs_path = \&fast_abs_path; | |
ac1ad7f0 PM |
396 | } |
397 | elsif ($^O eq 'os2') { | |
398 | # sys_cwd may keep the builtin command | |
96e4d5b1 | 399 | *cwd = defined &sys_cwd ? \&sys_cwd : \&_os2_cwd; |
400 | *getcwd = \&cwd; | |
401 | *fastgetcwd = \&cwd; | |
402 | *fastcwd = \&cwd; | |
403 | *abs_path = \&fast_abs_path; | |
ac1ad7f0 | 404 | } |
39e571d4 LM |
405 | elsif ($^O eq 'dos') { |
406 | *cwd = \&_dos_cwd; | |
407 | *getcwd = \&_dos_cwd; | |
408 | *fastgetcwd = \&_dos_cwd; | |
409 | *fastcwd = \&_dos_cwd; | |
96e4d5b1 | 410 | *abs_path = \&fast_abs_path; |
ac1ad7f0 | 411 | } |
7438b6ad | 412 | elsif ($^O =~ m/^(?:qnx|nto)$/ ) { |
7fbf1995 NA |
413 | *cwd = \&_qnx_cwd; |
414 | *getcwd = \&_qnx_cwd; | |
415 | *fastgetcwd = \&_qnx_cwd; | |
416 | *fastcwd = \&_qnx_cwd; | |
417 | *abs_path = \&_qnx_abs_path; | |
418 | *fast_abs_path = \&_qnx_abs_path; | |
419 | } | |
4fabb596 | 420 | elsif ($^O eq 'cygwin') { |
1cab015a EF |
421 | *getcwd = \&cwd; |
422 | *fastgetcwd = \&cwd; | |
423 | *fastcwd = \&cwd; | |
424 | *abs_path = \&fast_abs_path; | |
425 | } | |
ed79a026 | 426 | elsif ($^O eq 'epoc') { |
fa6a1c44 OF |
427 | *cwd = \&_epoc_cwd; |
428 | *getcwd = \&_epoc_cwd; | |
ed79a026 OF |
429 | *fastgetcwd = \&_epoc_cwd; |
430 | *fastcwd = \&_epoc_cwd; | |
431 | *abs_path = \&fast_abs_path; | |
432 | } | |
4aecb5b5 JH |
433 | elsif ($^O eq 'MacOS') { |
434 | *getcwd = \&cwd; | |
435 | *fastgetcwd = \&cwd; | |
436 | *fastcwd = \&cwd; | |
437 | *abs_path = \&fast_abs_path; | |
438 | } | |
55497cff | 439 | } |
4633a7c4 LW |
440 | |
441 | # package main; eval join('',<DATA>) || die $@; # quick test | |
442 | ||
a0d0e21e LW |
443 | 1; |
444 | ||
4633a7c4 LW |
445 | __END__ |
446 | BEGIN { import Cwd qw(:DEFAULT chdir); } | |
447 | print join("\n", cwd, getcwd, fastcwd, ""); | |
448 | chdir('..'); | |
449 | print join("\n", cwd, getcwd, fastcwd, ""); | |
450 | print "$ENV{PWD}\n"; |