1Path(3) User Contributed Perl Documentation Path(3)
2
6 File::Path - Create or remove directory trees
7
9 This document describes version 2.09 of File::Path, released
10 2013-01-17.
11
13 use File::Path qw(make_path remove_tree);
14 make_path('foo/bar/baz', '/zug/zwang');
16 make_path('foo/bar/baz', '/zug/zwang', {
17 verbose => 1,
18 mode => 0711,
19 });
20 remove_tree('foo/bar/baz', '/zug/zwang');
22 remove_tree('foo/bar/baz', '/zug/zwang', {
23 verbose => 1,
24 error => \my $err_list,
25 });
26 # legacy (interface promoted before v2.00)
28 mkpath('/foo/bar/baz');
29 mkpath('/foo/bar/baz', 1, 0711);
30 mkpath(['/foo/bar/baz', 'blurfl/quux'], 1, 0711);
31 rmtree('foo/bar/baz', 1, 1);
32 rmtree(['foo/bar/baz', 'blurfl/quux'], 1, 1);
33 # legacy (interface promoted before v2.06)
35 mkpath('foo/bar/baz', '/zug/zwang', { verbose => 1, mode => 0711 });
36 rmtree('foo/bar/baz', '/zug/zwang', { verbose => 1, mode => 0711 });
37
39 This module provide a convenient way to create directories of arbitrary
40 depth and to delete an entire directory subtree from the filesystem.
41 The following functions are provided:
43 make_path( $dir1, $dir2, .... )
45 make_path( $dir1, $dir2, ...., \%opts )
46 The "make_path" function creates the given directories if they
47 don't exists before, much like the Unix command "mkdir -p".
48 The function accepts a list of directories to be created. Its
50 behaviour may be tuned by an optional hashref appearing as the last
51 parameter on the call.
52 The function returns the list of directories actually created
54 during the call; in scalar context the number of directories
55 created.
56 The following keys are recognised in the option hash:
58 mode => $num
60 The numeric permissions mode to apply to each created directory
61 (defaults to 0777), to be modified by the current "umask". If
62 the directory already exists (and thus does not need to be
63 created), the permissions will not be modified.
64 "mask" is recognised as an alias for this parameter.
66 verbose => $bool
68 If present, will cause "make_path" to print the name of each
69 directory as it is created. By default nothing is printed.
70 error => \$err
72 If present, it should be a reference to a scalar. This scalar
73 will be made to reference an array, which will be used to store
74 any errors that are encountered. See the "ERROR HANDLING"
75 section for more information.
76 If this parameter is not used, certain error conditions may
78 raise a fatal error that will cause the program will halt,
79 unless trapped in an "eval" block.
80 owner => $owner
82 user => $owner
83 uid => $owner
84 If present, will cause any created directory to be owned by
85 $owner. If the value is numeric, it will be interpreted as a
86 uid, otherwise as username is assumed. An error will be issued
87 if the username cannot be mapped to a uid, or the uid does not
88 exist, or the process lacks the privileges to change ownership.
89 Ownwership of directories that already exist will not be
91 changed.
92 "user" and "uid" are aliases of "owner".
94 group => $group
96 If present, will cause any created directory to be owned by the
97 group $group. If the value is numeric, it will be interpreted
98 as a gid, otherwise as group name is assumed. An error will be
99 issued if the group name cannot be mapped to a gid, or the gid
100 does not exist, or the process lacks the privileges to change
101 group ownership.
102 Group ownwership of directories that already exist will not be
104 changed.
105 make_path '/var/tmp/webcache', {owner=>'nobody', group=>'nogroup'};
107 mkpath( $dir )
109 mkpath( $dir, $verbose, $mode )
110 mkpath( [$dir1, $dir2,...], $verbose, $mode )
111 mkpath( $dir1, $dir2,..., \%opt )
112 The mkpath() function provide the legacy interface of make_path()
113 with a different interpretation of the arguments passed. The
114 behaviour and return value of the function is otherwise identical
115 to make_path().
116 remove_tree( $dir1, $dir2, .... )
118 remove_tree( $dir1, $dir2, ...., \%opts )
119 The "remove_tree" function deletes the given directories and any
120 files and subdirectories they might contain, much like the Unix
121 command "rm -r" or "del /s" on Windows.
122 The function accepts a list of directories to be removed. Its
124 behaviour may be tuned by an optional hashref appearing as the last
125 parameter on the call.
126 The functions returns the number of files successfully deleted.
128 The following keys are recognised in the option hash:
130 verbose => $bool
132 If present, will cause "remove_tree" to print the name of each
133 file as it is unlinked. By default nothing is printed.
134 safe => $bool
136 When set to a true value, will cause "remove_tree" to skip the
137 files for which the process lacks the required privileges
138 needed to delete files, such as delete privileges on VMS. In
139 other words, the code will make no attempt to alter file
140 permissions. Thus, if the process is interrupted, no filesystem
141 object will be left in a more permissive mode.
142 keep_root => $bool
144 When set to a true value, will cause all files and
145 subdirectories to be removed, except the initially specified
146 directories. This comes in handy when cleaning out an
147 application's scratch directory.
148 remove_tree( '/tmp', {keep_root => 1} );
150 result => \$res
152 If present, it should be a reference to a scalar. This scalar
153 will be made to reference an array, which will be used to store
154 all files and directories unlinked during the call. If nothing
155 is unlinked, the array will be empty.
156 remove_tree( '/tmp', {result => \my $list} );
158 print "unlinked $_\n" for @$list;
159 This is a useful alternative to the "verbose" key.
161 error => \$err
163 If present, it should be a reference to a scalar. This scalar
164 will be made to reference an array, which will be used to store
165 any errors that are encountered. See the "ERROR HANDLING"
166 section for more information.
167 Removing things is a much more dangerous proposition than
169 creating things. As such, there are certain conditions that
170 "remove_tree" may encounter that are so dangerous that the only
171 sane action left is to kill the program.
172 Use "error" to trap all that is reasonable (problems with
174 permissions and the like), and let it die if things get out of
175 hand. This is the safest course of action.
176 rmtree( $dir )
178 rmtree( $dir, $verbose, $safe )
179 rmtree( [$dir1, $dir2,...], $verbose, $safe )
180 rmtree( $dir1, $dir2,..., \%opt )
181 The rmtree() function provide the legacy interface of remove_tree()
182 with a different interpretation of the arguments passed. The
183 behaviour and return value of the function is otherwise identical
184 to remove_tree().
185 ERROR HANDLING
187 NOTE:
188 The following error handling mechanism is considered experimental
189 and is subject to change pending feedback from users.
190 If "make_path" or "remove_tree" encounter an error, a diagnostic
192 message will be printed to "STDERR" via "carp" (for non-fatal errors),
193 or via "croak" (for fatal errors).
194 If this behaviour is not desirable, the "error" attribute may be used
196 to hold a reference to a variable, which will be used to store the
197 diagnostics. The variable is made a reference to an array of hash
198 references. Each hash contain a single key/value pair where the key is
199 the name of the file, and the value is the error message (including the
200 contents of $! when appropriate). If a general error is encountered
201 the diagnostic key will be empty.
202 An example usage looks like:
204 remove_tree( 'foo/bar', 'bar/rat', {error => \my $err} );
206 if (@$err) {
207 for my $diag (@$err) {
208 my ($file, $message) = %$diag;
209 if ($file eq '') {
210 print "general error: $message\n";
211 }
212 else {
213 print "problem unlinking $file: $message\n";
214 }
215 }
216 }
217 else {
218 print "No error encountered\n";
219 }
220 Note that if no errors are encountered, $err will reference an empty
222 array. This means that $err will always end up TRUE; so you need to
223 test @$err to determine if errors occured.
224 NOTES
226 "File::Path" blindly exports "mkpath" and "rmtree" into the current
227 namespace. These days, this is considered bad style, but to change it
228 now would break too much code. Nonetheless, you are invited to specify
229 what it is you are expecting to use:
230 use File::Path 'rmtree';
232 The routines "make_path" and "remove_tree" are not exported by default.
234 You must specify which ones you want to use.
235 use File::Path 'remove_tree';
237 Note that a side-effect of the above is that "mkpath" and "rmtree" are
239 no longer exported at all. This is due to the way the "Exporter" module
240 works. If you are migrating a codebase to use the new interface, you
241 will have to list everything explicitly. But that's just good practice
242 anyway.
243 use File::Path qw(remove_tree rmtree);
245 API CHANGES
247 The API was changed in the 2.0 branch. For a time, "mkpath" and
249 "rmtree" tried, unsuccessfully, to deal with the two different calling
250 mechanisms. This approach was considered a failure.
251 The new semantics are now only available with "make_path" and
253 "remove_tree". The old semantics are only available through "mkpath"
254 and "rmtree". Users are strongly encouraged to upgrade to at least 2.08
255 in order to avoid surprises.
256 SECURITY CONSIDERATIONS
258 There were race conditions 1.x implementations of File::Path's "rmtree"
260 function (although sometimes patched depending on the OS distribution
261 or platform). The 2.0 version contains code to avoid the problem
262 mentioned in CVE-2002-0435.
263 See the following pages for more information:
265 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=286905
267 http://www.nntp.perl.org/group/perl.perl5.porters/2005/01/msg97623.html
268 http://www.debian.org/security/2005/dsa-696
269 Additionally, unless the "safe" parameter is set (or the third
271 parameter in the traditional interface is TRUE), should a "remove_tree"
272 be interrupted, files that were originally in read-only mode may now
273 have their permissions set to a read-write (or "delete OK") mode.
274
276 FATAL errors will cause the program to halt ("croak"), since the
277 problem is so severe that it would be dangerous to continue. (This can
278 always be trapped with "eval", but it's not a good idea. Under the
279 circumstances, dying is the best thing to do).
280 SEVERE errors may be trapped using the modern interface. If the they
282 are not trapped, or the old interface is used, such an error will cause
283 the program will halt.
284 All other errors may be trapped using the modern interface, otherwise
286 they will be "carp"ed about. Program execution will not be halted.
287 mkdir [path]: [errmsg] (SEVERE)
289 "make_path" was unable to create the path. Probably some sort of
290 permissions error at the point of departure, or insufficient
291 resources (such as free inodes on Unix).
292 No root path(s) specified
294 "make_path" was not given any paths to create. This message is only
295 emitted if the routine is called with the traditional interface.
296 The modern interface will remain silent if given nothing to do.
297 No such file or directory
299 On Windows, if "make_path" gives you this warning, it may mean that
300 you have exceeded your filesystem's maximum path length.
301 cannot fetch initial working directory: [errmsg]
303 "remove_tree" attempted to determine the initial directory by
304 calling "Cwd::getcwd", but the call failed for some reason. No
305 attempt will be made to delete anything.
306 cannot stat initial working directory: [errmsg]
308 "remove_tree" attempted to stat the initial directory (after having
309 successfully obtained its name via "getcwd"), however, the call
310 failed for some reason. No attempt will be made to delete anything.
311 cannot chdir to [dir]: [errmsg]
313 "remove_tree" attempted to set the working directory in order to
314 begin deleting the objects therein, but was unsuccessful. This is
315 usually a permissions issue. The routine will continue to delete
316 other things, but this directory will be left intact.
317 directory [dir] changed before chdir, expected dev=[n] ino=[n], actual
319 dev=[n] ino=[n], aborting. (FATAL)
320 "remove_tree" recorded the device and inode of a directory, and
321 then moved into it. It then performed a "stat" on the current
322 directory and detected that the device and inode were no longer the
323 same. As this is at the heart of the race condition problem, the
324 program will die at this point.
325 cannot make directory [dir] read+writeable: [errmsg]
327 "remove_tree" attempted to change the permissions on the current
328 directory to ensure that subsequent unlinkings would not run into
329 problems, but was unable to do so. The permissions remain as they
330 were, and the program will carry on, doing the best it can.
331 cannot read [dir]: [errmsg]
333 "remove_tree" tried to read the contents of the directory in order
334 to acquire the names of the directory entries to be unlinked, but
335 was unsuccessful. This is usually a permissions issue. The program
336 will continue, but the files in this directory will remain after
337 the call.
338 cannot reset chmod [dir]: [errmsg]
340 "remove_tree", after having deleted everything in a directory,
341 attempted to restore its permissions to the original state but
342 failed. The directory may wind up being left behind.
343 cannot remove [dir] when cwd is [dir]
345 The current working directory of the program is /some/path/to/here
346 and you are attempting to remove an ancestor, such as /some/path.
347 The directory tree is left untouched.
348 The solution is to "chdir" out of the child directory to a place
350 outside the directory tree to be removed.
351 cannot chdir to [parent-dir] from [child-dir]: [errmsg], aborting.
353 (FATAL)
354 "remove_tree", after having deleted everything and restored the
355 permissions of a directory, was unable to chdir back to the parent.
356 The program halts to avoid a race condition from occurring.
357 cannot stat prior working directory [dir]: [errmsg], aborting. (FATAL)
359 "remove_tree" was unable to stat the parent directory after have
360 returned from the child. Since there is no way of knowing if we
361 returned to where we think we should be (by comparing device and
362 inode) the only way out is to "croak".
363 previous directory [parent-dir] changed before entering [child-dir],
365 expected dev=[n] ino=[n], actual dev=[n] ino=[n], aborting. (FATAL)
366 When "remove_tree" returned from deleting files in a child
367 directory, a check revealed that the parent directory it returned
368 to wasn't the one it started out from. This is considered a sign of
369 malicious activity.
370 cannot make directory [dir] writeable: [errmsg]
372 Just before removing a directory (after having successfully removed
373 everything it contained), "remove_tree" attempted to set the
374 permissions on the directory to ensure it could be removed and
375 failed. Program execution continues, but the directory may possibly
376 not be deleted.
377 cannot remove directory [dir]: [errmsg]
379 "remove_tree" attempted to remove a directory, but failed. This may
380 because some objects that were unable to be removed remain in the
381 directory, or a permissions issue. The directory will be left
382 behind.
383 cannot restore permissions of [dir] to [0nnn]: [errmsg]
385 After having failed to remove a directory, "remove_tree" was unable
386 to restore its permissions from a permissive state back to a
387 possibly more restrictive setting. (Permissions given in octal).
388 cannot make file [file] writeable: [errmsg]
390 "remove_tree" attempted to force the permissions of a file to
391 ensure it could be deleted, but failed to do so. It will, however,
392 still attempt to unlink the file.
393 cannot unlink file [file]: [errmsg]
395 "remove_tree" failed to remove a file. Probably a permissions
396 issue.
397 cannot restore permissions of [file] to [0nnn]: [errmsg]
399 After having failed to remove a file, "remove_tree" was also unable
400 to restore the permissions on the file to a possibly less
401 permissive setting. (Permissions given in octal).
402 unable to map [owner] to a uid, ownership not changed");
404 "make_path" was instructed to give the ownership of created
405 directories to the symbolic name [owner], but "getpwnam" did not
406 return the corresponding numeric uid. The directory will be
407 created, but ownership will not be changed.
408 unable to map [group] to a gid, group ownership not changed
410 "make_path" was instructed to give the group ownership of created
411 directories to the symbolic name [group], but "getgrnam" did not
412 return the corresponding numeric gid. The directory will be
413 created, but group ownership will not be changed.
414
416 · File::Remove
417 Allows files and directories to be moved to the Trashcan/Recycle
419 Bin (where they may later be restored if necessary) if the
420 operating system supports such functionality. This feature may one
421 day be made available directly in "File::Path".
422 · File::Find::Rule
424 When removing directory trees, if you want to examine each file to
426 decide whether to delete it (and possibly leaving large swathes
427 alone), File::Find::Rule offers a convenient and flexible approach
428 to examining directory trees.
429
431 Please report all bugs on the RT queue:
432 <http://rt.cpan.org/NoAuth/Bugs.html?Dist=File-Path>
434 You can also send pull requests to the Github repository:
436 <https://github.com/dland/File-Path>
438
440 Paul Szabo identified the race condition originally, and Brendan O'Dea
441 wrote an implementation for Debian that addressed the problem. That
442 code was used as a basis for the current code. Their efforts are
443 greatly appreciated.
444 Gisle Aas made a number of improvements to the documentation for 2.07
446 and his advice and assistance is also greatly appreciated.
447
449 Tim Bunce and Charles Bailey. Currently maintained by David Landgren
450 <david@landgren.net>.
451
453 This module is copyright (C) Charles Bailey, Tim Bunce and David
454 Landgren 1995-2013. All rights reserved.
455
457 This library is free software; you can redistribute it and/or modify it
458 under the same terms as Perl itself.
459perl v5.16.3 2013-01-16 Path(3)