1Archive::Tar(3) User Contributed Perl Documentation Archive::Tar(3)
2
6 Archive::Tar - module for manipulations of tar archives
7
9 use Archive::Tar;
10 my $tar = Archive::Tar->new;
11 $tar->read('origin.tgz');
13 $tar->extract();
14 $tar->add_files('file/foo.pl', 'docs/README');
16 $tar->add_data('file/baz.txt', 'This is the contents now');
17 $tar->rename('oldname', 'new/file/name');
19 $tar->chown('/', 'root');
20 $tar->chown('/', 'root:root');
21 $tar->chmod('/tmp', '1777');
22 $tar->write('files.tar'); # plain tar
24 $tar->write('files.tgz', COMPRESS_GZIP); # gzip compressed
25 $tar->write('files.tbz', COMPRESS_BZIP); # bzip2 compressed
26 $tar->write('files.txz', COMPRESS_XZ); # xz compressed
27
29 Archive::Tar provides an object oriented mechanism for handling tar
30 files. It provides class methods for quick and easy files handling
31 while also allowing for the creation of tar file objects for custom
32 manipulation. If you have the IO::Zlib module installed, Archive::Tar
33 will also support compressed or gzipped tar files.
34 An object of class Archive::Tar represents a .tar(.gz) archive full of
36 files and things.
37
39 Archive::Tar->new( [$file, $compressed] )
40 Returns a new Tar object. If given any arguments, new() calls the
41 read() method automatically, passing on the arguments provided to the
42 read() method.
43 If new() is invoked with arguments and the read() method fails for any
45 reason, new() returns undef.
46 $tar->read ( $filename|$handle, [$compressed, {opt => 'val'}] )
48 Read the given tar file into memory. The first argument can either be
49 the name of a file or a reference to an already open filehandle (or an
50 IO::Zlib object if it's compressed)
51 The "read" will replace any previous content in $tar!
53 The second argument may be considered optional, but remains for
55 backwards compatibility. Archive::Tar now looks at the file magic to
56 determine what class should be used to open the file and will
57 transparently Do The Right Thing.
58 Archive::Tar will warn if you try to pass a bzip2 / xz compressed file
60 and the IO::Uncompress::Bunzip2 / IO::Uncompress::UnXz are not
61 available and simply return.
62 Note that you can currently not pass a "gzip" compressed filehandle,
64 which is not opened with "IO::Zlib", a "bzip2" compressed filehandle,
65 which is not opened with "IO::Uncompress::Bunzip2", a "xz" compressed
66 filehandle, which is not opened with "IO::Uncompress::UnXz", nor a
67 string containing the full archive information (either compressed or
68 uncompressed). These are worth while features, but not currently
69 implemented. See the "TODO" section.
70 The third argument can be a hash reference with options. Note that all
72 options are case-sensitive.
73 limit
75 Do not read more than "limit" files. This is useful if you have
76 very big archives, and are only interested in the first few files.
77 filter
79 Can be set to a regular expression. Only files with names that
80 match the expression will be read.
81 md5 Set to 1 and the md5sum of files will be returned (instead of file
83 data)
84 my $iter = Archive::Tar->iter( $file, 1, {md5 => 1} );
85 while( my $f = $iter->() ) {
86 print $f->data . "\t" . $f->full_path . $/;
87 }
88 extract
90 If set to true, immediately extract entries when reading them. This
91 gives you the same memory break as the "extract_archive" function.
92 Note however that entries will not be read into memory, but written
93 straight to disk. This means no "Archive::Tar::File" objects are
94 created for you to inspect.
95 All files are stored internally as "Archive::Tar::File" objects.
97 Please consult the Archive::Tar::File documentation for details.
98 Returns the number of files read in scalar context, and a list of
100 "Archive::Tar::File" objects in list context.
101 $tar->contains_file( $filename )
103 Check if the archive contains a certain file. It will return true if
104 the file is in the archive, false otherwise.
105 Note however, that this function does an exact match using "eq" on the
107 full path. So it cannot compensate for case-insensitive file- systems
108 or compare 2 paths to see if they would point to the same underlying
109 file.
110 $tar->extract( [@filenames] )
112 Write files whose names are equivalent to any of the names in
113 @filenames to disk, creating subdirectories as necessary. This might
114 not work too well under VMS. Under MacPerl, the file's modification
115 time will be converted to the MacOS zero of time, and appropriate
116 conversions will be done to the path. However, the length of each
117 element of the path is not inspected to see whether it's longer than
118 MacOS currently allows (32 characters).
119 If "extract" is called without a list of file names, the entire
121 contents of the archive are extracted.
122 Returns a list of filenames extracted.
124 $tar->extract_file( $file, [$extract_path] )
126 Write an entry, whose name is equivalent to the file name provided to
127 disk. Optionally takes a second parameter, which is the full native
128 path (including filename) the entry will be written to.
129 For example:
131 $tar->extract_file( 'name/in/archive', 'name/i/want/to/give/it' );
133 $tar->extract_file( $at_file_object, 'name/i/want/to/give/it' );
135 Returns true on success, false on failure.
137 $tar->list_files( [\@properties] )
139 Returns a list of the names of all the files in the archive.
140 If list_files() is passed an array reference as its first argument it
142 returns a list of hash references containing the requested properties
143 of each file. The following list of properties is supported: name,
144 size, mtime (last modified date), mode, uid, gid, linkname, uname,
145 gname, devmajor, devminor, prefix.
146 Passing an array reference containing only one element, 'name', is
148 special cased to return a list of names rather than a list of hash
149 references, making it equivalent to calling "list_files" without
150 arguments.
151 $tar->get_files( [@filenames] )
153 Returns the "Archive::Tar::File" objects matching the filenames
154 provided. If no filename list was passed, all "Archive::Tar::File"
155 objects in the current Tar object are returned.
156 Please refer to the "Archive::Tar::File" documentation on how to handle
158 these objects.
159 $tar->get_content( $file )
161 Return the content of the named file.
162 $tar->replace_content( $file, $content )
164 Make the string $content be the content for the file named $file.
165 $tar->rename( $file, $new_name )
167 Rename the file of the in-memory archive to $new_name.
168 Note that you must specify a Unix path for $new_name, since per tar
170 standard, all files in the archive must be Unix paths.
171 Returns true on success and false on failure.
173 $tar->chmod( $file, $mode )
175 Change mode of $file to $mode.
176 Returns true on success and false on failure.
178 $tar->chown( $file, $uname [, $gname] )
180 Change owner $file to $uname and $gname.
181 Returns true on success and false on failure.
183 $tar->remove (@filenamelist)
185 Removes any entries with names matching any of the given filenames from
186 the in-memory archive. Returns a list of "Archive::Tar::File" objects
187 that remain.
188 $tar->clear
190 "clear" clears the current in-memory archive. This effectively gives
191 you a 'blank' object, ready to be filled again. Note that "clear" only
192 has effect on the object, not the underlying tarfile.
193 $tar->write ( [$file, $compressed, $prefix] )
195 Write the in-memory archive to disk. The first argument can either be
196 the name of a file or a reference to an already open filehandle (a GLOB
197 reference).
198 The second argument is used to indicate compression. You can compress
200 using "gzip", "bzip2" or "xz". If you pass a digit, it's assumed to be
201 the "gzip" compression level (between 1 and 9), but the use of
202 constants is preferred:
203 # write a gzip compressed file
205 $tar->write( 'out.tgz', COMPRESS_GZIP );
206 # write a bzip compressed file
208 $tar->write( 'out.tbz', COMPRESS_BZIP );
209 # write a xz compressed file
211 $tar->write( 'out.txz', COMPRESS_XZ );
212 Note that when you pass in a filehandle, the compression argument is
214 ignored, as all files are printed verbatim to your filehandle. If you
215 wish to enable compression with filehandles, use an "IO::Zlib",
216 "IO::Compress::Bzip2" or "IO::Compress::Xz" filehandle instead.
217 The third argument is an optional prefix. All files will be tucked away
219 in the directory you specify as prefix. So if you have files 'a' and
220 'b' in your archive, and you specify 'foo' as prefix, they will be
221 written to the archive as 'foo/a' and 'foo/b'.
222 If no arguments are given, "write" returns the entire formatted archive
224 as a string, which could be useful if you'd like to stuff the archive
225 into a socket or a pipe to gzip or something.
226 $tar->add_files( @filenamelist )
228 Takes a list of filenames and adds them to the in-memory archive.
229 The path to the file is automatically converted to a Unix like
231 equivalent for use in the archive, and, if on MacOS, the file's
232 modification time is converted from the MacOS epoch to the Unix epoch.
233 So tar archives created on MacOS with Archive::Tar can be read both
234 with tar on Unix and applications like suntar or Stuffit Expander on
235 MacOS.
236 Be aware that the file's type/creator and resource fork will be lost,
238 which is usually what you want in cross-platform archives.
239 Instead of a filename, you can also pass it an existing
241 "Archive::Tar::File" object from, for example, another archive. The
242 object will be clone, and effectively be a copy of the original, not an
243 alias.
244 Returns a list of "Archive::Tar::File" objects that were just added.
246 $tar->add_data ( $filename, $data, [$opthashref] )
248 Takes a filename, a scalar full of data and optionally a reference to a
249 hash with specific options.
250 Will add a file to the in-memory archive, with name $filename and
252 content $data. Specific properties can be set using $opthashref. The
253 following list of properties is supported: name, size, mtime (last
254 modified date), mode, uid, gid, linkname, uname, gname, devmajor,
255 devminor, prefix, type. (On MacOS, the file's path and modification
256 times are converted to Unix equivalents.)
257 Valid values for the file type are the following constants defined by
259 Archive::Tar::Constant:
260 FILE
262 Regular file.
263 HARDLINK
265 SYMLINK
266 Hard and symbolic ("soft") links; linkname should specify target.
267 CHARDEV
269 BLOCKDEV
270 Character and block devices. devmajor and devminor should specify
271 the major and minor device numbers.
272 DIR Directory.
274 FIFO
276 FIFO (named pipe).
277 SOCKET
279 Socket.
280 Returns the "Archive::Tar::File" object that was just added, or "undef"
282 on failure.
283 $tar->error( [$BOOL] )
285 Returns the current error string (usually, the last error reported).
286 If a true value was specified, it will give the "Carp::longmess"
287 equivalent of the error, in effect giving you a stacktrace.
288 For backwards compatibility, this error is also available as
290 $Archive::Tar::error although it is much recommended you use the method
291 call instead.
292 $tar->setcwd( $cwd );
294 "Archive::Tar" needs to know the current directory, and it will run
295 Cwd::cwd() every time it extracts a relative entry from the tarfile and
296 saves it in the file system. (As of version 1.30, however,
297 "Archive::Tar" will use the speed optimization described below
298 automatically, so it's only relevant if you're using extract_file()).
299 Since "Archive::Tar" doesn't change the current directory internally
301 while it is extracting the items in a tarball, all calls to Cwd::cwd()
302 can be avoided if we can guarantee that the current directory doesn't
303 get changed externally.
304 To use this performance boost, set the current directory via
306 use Cwd;
308 $tar->setcwd( cwd() );
309 once before calling a function like "extract_file" and "Archive::Tar"
311 will use the current directory setting from then on and won't call
312 Cwd::cwd() internally.
313 To switch back to the default behaviour, use
315 $tar->setcwd( undef );
317 and "Archive::Tar" will call Cwd::cwd() internally again.
319 If you're using "Archive::Tar"'s extract() method, setcwd() will be
321 called for you.
322
324 Archive::Tar->create_archive($file, $compressed, @filelist)
325 Creates a tar file from the list of files provided. The first argument
326 can either be the name of the tar file to create or a reference to an
327 open file handle (e.g. a GLOB reference).
328 The second argument is used to indicate compression. You can compress
330 using "gzip", "bzip2" or "xz". If you pass a digit, it's assumed to be
331 the "gzip" compression level (between 1 and 9), but the use of
332 constants is preferred:
333 # write a gzip compressed file
335 Archive::Tar->create_archive( 'out.tgz', COMPRESS_GZIP, @filelist );
336 # write a bzip compressed file
338 Archive::Tar->create_archive( 'out.tbz', COMPRESS_BZIP, @filelist );
339 # write a xz compressed file
341 Archive::Tar->create_archive( 'out.txz', COMPRESS_XZ, @filelist );
342 Note that when you pass in a filehandle, the compression argument is
344 ignored, as all files are printed verbatim to your filehandle. If you
345 wish to enable compression with filehandles, use an "IO::Zlib",
346 "IO::Compress::Bzip2" or "IO::Compress::Xz" filehandle instead.
347 The remaining arguments list the files to be included in the tar file.
349 These files must all exist. Any files which don't exist or can't be
350 read are silently ignored.
351 If the archive creation fails for any reason, "create_archive" will
353 return false. Please use the "error" method to find the cause of the
354 failure.
355 Note that this method does not write "on the fly" as it were; it still
357 reads all the files into memory before writing out the archive.
358 Consult the FAQ below if this is a problem.
359 Archive::Tar->iter( $filename, [ $compressed, {opt => $val} ] )
361 Returns an iterator function that reads the tar file without loading it
362 all in memory. Each time the function is called it will return the
363 next file in the tarball. The files are returned as
364 "Archive::Tar::File" objects. The iterator function returns the empty
365 list once it has exhausted the files contained.
366 The second argument can be a hash reference with options, which are
368 identical to the arguments passed to read().
369 Example usage:
371 my $next = Archive::Tar->iter( "example.tar.gz", 1, {filter => qr/\.pm$/} );
373 while( my $f = $next->() ) {
375 print $f->name, "\n";
376 $f->extract or warn "Extraction failed";
378 # ....
380 }
381 Archive::Tar->list_archive($file, $compressed, [\@properties])
383 Returns a list of the names of all the files in the archive. The first
384 argument can either be the name of the tar file to list or a reference
385 to an open file handle (e.g. a GLOB reference).
386 If list_archive() is passed an array reference as its third argument it
388 returns a list of hash references containing the requested properties
389 of each file. The following list of properties is supported:
390 full_path, name, size, mtime (last modified date), mode, uid, gid,
391 linkname, uname, gname, devmajor, devminor, prefix, type.
392 See "Archive::Tar::File" for details about supported properties.
394 Passing an array reference containing only one element, 'name', is
396 special cased to return a list of names rather than a list of hash
397 references.
398 Archive::Tar->extract_archive($file, $compressed)
400 Extracts the contents of the tar file. The first argument can either
401 be the name of the tar file to create or a reference to an open file
402 handle (e.g. a GLOB reference). All relative paths in the tar file
403 will be created underneath the current working directory.
404 "extract_archive" will return a list of files it extracted. If the
406 archive extraction fails for any reason, "extract_archive" will return
407 false. Please use the "error" method to find the cause of the failure.
408 $bool = Archive::Tar->has_io_string
410 Returns true if we currently have "IO::String" support loaded.
411 Either "IO::String" or "perlio" support is needed to support writing
413 stringified archives. Currently, "perlio" is the preferred method, if
414 available.
415 See the "GLOBAL VARIABLES" section to see how to change this
417 preference.
418 $bool = Archive::Tar->has_perlio
420 Returns true if we currently have "perlio" support loaded.
421 This requires "perl-5.8" or higher, compiled with "perlio"
423 Either "IO::String" or "perlio" support is needed to support writing
425 stringified archives. Currently, "perlio" is the preferred method, if
426 available.
427 See the "GLOBAL VARIABLES" section to see how to change this
429 preference.
430 $bool = Archive::Tar->has_zlib_support
432 Returns true if "Archive::Tar" can extract "zlib" compressed archives
433 $bool = Archive::Tar->has_bzip2_support
435 Returns true if "Archive::Tar" can extract "bzip2" compressed archives
436 $bool = Archive::Tar->has_xz_support
438 Returns true if "Archive::Tar" can extract "xz" compressed archives
439 Archive::Tar->can_handle_compressed_files
441 A simple checking routine, which will return true if "Archive::Tar" is
442 able to uncompress compressed archives on the fly with "IO::Zlib",
443 "IO::Compress::Bzip2" and "IO::Compress::Xz" or false if not both are
444 installed.
445 You can use this as a shortcut to determine whether "Archive::Tar" will
447 do what you think before passing compressed archives to its "read"
448 method.
449
451 $Archive::Tar::FOLLOW_SYMLINK
452 Set this variable to 1 to make "Archive::Tar" effectively make a copy
453 of the file when extracting. Default is 0, which means the symlink
454 stays intact. Of course, you will have to pack the file linked to as
455 well.
456 This option is checked when you write out the tarfile using "write" or
458 "create_archive".
459 This works just like "/bin/tar"'s "-h" option.
461 $Archive::Tar::CHOWN
463 By default, "Archive::Tar" will try to "chown" your files if it is able
464 to. In some cases, this may not be desired. In that case, set this
465 variable to 0 to disable "chown"-ing, even if it were possible.
466 The default is 1.
468 $Archive::Tar::CHMOD
470 By default, "Archive::Tar" will try to "chmod" your files to whatever
471 mode was specified for the particular file in the archive. In some
472 cases, this may not be desired. In that case, set this variable to 0 to
473 disable "chmod"-ing.
474 The default is 1.
476 $Archive::Tar::SAME_PERMISSIONS
478 When, $Archive::Tar::CHMOD is enabled, this setting controls whether
479 the permissions on files from the archive are used without modification
480 of if they are filtered by removing any setid bits and applying the
481 current umask.
482 The default is 1 for the root user and 0 for normal users.
484 $Archive::Tar::DO_NOT_USE_PREFIX
486 By default, "Archive::Tar" will try to put paths that are over 100
487 characters in the "prefix" field of your tar header, as defined per
488 POSIX-standard. However, some (older) tar programs do not implement
489 this spec. To retain compatibility with these older or non-POSIX
490 compliant versions, you can set the $DO_NOT_USE_PREFIX variable to a
491 true value, and "Archive::Tar" will use an alternate way of dealing
492 with paths over 100 characters by using the "GNU Extended Header"
493 feature.
494 Note that clients who do not support the "GNU Extended Header" feature
496 will not be able to read these archives. Such clients include tars on
497 "Solaris", "Irix" and "AIX".
498 The default is 0.
500 $Archive::Tar::DEBUG
502 Set this variable to 1 to always get the "Carp::longmess" output of the
503 warnings, instead of the regular "carp". This is the same message you
504 would get by doing:
505 $tar->error(1);
507 Defaults to 0.
509 $Archive::Tar::WARN
511 Set this variable to 0 if you do not want any warnings printed.
512 Personally I recommend against doing this, but people asked for the
513 option. Also, be advised that this is of course not threadsafe.
514 Defaults to 1.
516 $Archive::Tar::error
518 Holds the last reported error. Kept for historical reasons, but its use
519 is very much discouraged. Use the error() method instead:
520 warn $tar->error unless $tar->extract;
522 Note that in older versions of this module, the error() method would
524 return an effectively global value even when called an instance method
525 as above. This has since been fixed, and multiple instances of
526 "Archive::Tar" now have separate error strings.
527 $Archive::Tar::INSECURE_EXTRACT_MODE
529 This variable indicates whether "Archive::Tar" should allow files to be
530 extracted outside their current working directory.
531 Allowing this could have security implications, as a malicious tar
533 archive could alter or replace any file the extracting user has
534 permissions to. Therefor, the default is to not allow insecure
535 extractions.
536 If you trust the archive, or have other reasons to allow the archive to
538 write files outside your current working directory, set this variable
539 to "true".
540 Note that this is a backwards incompatible change from version 1.36 and
542 before.
543 $Archive::Tar::HAS_PERLIO
545 This variable holds a boolean indicating if we currently have "perlio"
546 support loaded. This will be enabled for any perl greater than 5.8
547 compiled with "perlio".
548 If you feel strongly about disabling it, set this variable to "false".
550 Note that you will then need "IO::String" installed to support writing
551 stringified archives.
552 Don't change this variable unless you really know what you're doing.
554 $Archive::Tar::HAS_IO_STRING
556 This variable holds a boolean indicating if we currently have
557 "IO::String" support loaded. This will be enabled for any perl that has
558 a loadable "IO::String" module.
559 If you feel strongly about disabling it, set this variable to "false".
561 Note that you will then need "perlio" support from your perl to be able
562 to write stringified archives.
563 Don't change this variable unless you really know what you're doing.
565 $Archive::Tar::ZERO_PAD_NUMBERS
567 This variable holds a boolean indicating if we will create zero padded
568 numbers for "size", "mtime" and "checksum". The default is 0,
569 indicating that we will create space padded numbers. Added for
570 compatibility with "busybox" implementations.
571 Tuning the way RESOLVE_SYMLINK will works
573 You can tune the behaviour by setting the
574 $Archive::Tar::RESOLVE_SYMLINK variable, or
575 $ENV{PERL5_AT_RESOLVE_SYMLINK} before loading the module Archive::Tar.
576 Values can be one of the following:
578 none
580 Disable this mechanism and failed as it was in previous version
581 (<1.88)
582 speed (default)
584 If you prefer speed this will read again the whole archive using
585 read() so all entries will be available
586 memory
588 If you prefer memory
589 Limitation: It won't work for terminal, pipe or sockets or every non
591 seekable source.
592 $Archive::Tar::EXTRACT_BLOCK_SIZE
594 This variable holds an integer with the block size that should be used
595 when writing files during extraction. It defaults to 1 GiB. Please note
596 that this cannot be arbitrarily large since some operating systems
597 limit the number of bytes that can be written in one call to write(2),
598 so if this is too large, extraction may fail with an error.
599
601 What's the minimum perl version required to run Archive::Tar?
602 You will need perl version 5.005_03 or newer.
603 Isn't Archive::Tar slow?
605 Yes it is. It's pure perl, so it's a lot slower then your
606 "/bin/tar" However, it's very portable. If speed is an issue,
607 consider using "/bin/tar" instead.
608 Isn't Archive::Tar heavier on memory than /bin/tar?
610 Yes it is, see previous answer. Since "Compress::Zlib" and
611 therefore "IO::Zlib" doesn't support "seek" on their filehandles,
612 there is little choice but to read the archive into memory. This
613 is ok if you want to do in-memory manipulation of the archive.
614 If you just want to extract, use the "extract_archive" class method
616 instead. It will optimize and write to disk immediately.
617 Another option is to use the "iter" class method to iterate over
619 the files in the tarball without reading them all in memory at
620 once.
621 Can you lazy-load data instead?
623 In some cases, yes. You can use the "iter" class method to iterate
624 over the files in the tarball without reading them all in memory at
625 once.
626 How much memory will an X kb tar file need?
628 Probably more than X kb, since it will all be read into memory. If
629 this is a problem, and you don't need to do in memory manipulation
630 of the archive, consider using the "iter" class method, or
631 "/bin/tar" instead.
632 What do you do with unsupported filetypes in an archive?
634 "Unix" has a few filetypes that aren't supported on other
635 platforms, like "Win32". If we encounter a "hardlink" or "symlink"
636 we'll just try to make a copy of the original file, rather than
637 throwing an error.
638 This does require you to read the entire archive in to memory
640 first, since otherwise we wouldn't know what data to fill the copy
641 with. (This means that you cannot use the class methods, including
642 "iter" on archives that have incompatible filetypes and still
643 expect things to work).
644 For other filetypes, like "chardevs" and "blockdevs" we'll warn
646 that the extraction of this particular item didn't work.
647 I'm using WinZip, or some other non-POSIX client, and files are not
649 being extracted properly!
650 By default, "Archive::Tar" is in a completely POSIX-compatible
651 mode, which uses the POSIX-specification of "tar" to store files.
652 For paths greater than 100 characters, this is done using the
653 "POSIX header prefix". Non-POSIX-compatible clients may not support
654 this part of the specification, and may only support the "GNU
655 Extended Header" functionality. To facilitate those clients, you
656 can set the $Archive::Tar::DO_NOT_USE_PREFIX variable to "true".
657 See the "GLOBAL VARIABLES" section for details on this variable.
658 Note that GNU tar earlier than version 1.14 does not cope well with
660 the "POSIX header prefix". If you use such a version, consider
661 setting the $Archive::Tar::DO_NOT_USE_PREFIX variable to "true".
662 How do I extract only files that have property X from an archive?
664 Sometimes, you might not wish to extract a complete archive, just
665 the files that are relevant to you, based on some criteria.
666 You can do this by filtering a list of "Archive::Tar::File" objects
668 based on your criteria. For example, to extract only files that
669 have the string "foo" in their title, you would use:
670 $tar->extract(
672 grep { $_->full_path =~ /foo/ } $tar->get_files
673 );
674 This way, you can filter on any attribute of the files in the
676 archive. Consult the "Archive::Tar::File" documentation on how to
677 use these objects.
678 How do I access .tar.Z files?
680 The "Archive::Tar" module can optionally use "Compress::Zlib" (via
681 the "IO::Zlib" module) to access tar files that have been
682 compressed with "gzip". Unfortunately tar files compressed with the
683 Unix "compress" utility cannot be read by "Compress::Zlib" and so
684 cannot be directly accesses by "Archive::Tar".
685 If the "uncompress" or "gunzip" programs are available, you can use
687 one of these workarounds to read ".tar.Z" files from "Archive::Tar"
688 Firstly with "uncompress"
690 use Archive::Tar;
692 open F, "uncompress -c $filename |";
694 my $tar = Archive::Tar->new(*F);
695 ...
696 and this with "gunzip"
698 use Archive::Tar;
700 open F, "gunzip -c $filename |";
702 my $tar = Archive::Tar->new(*F);
703 ...
704 Similarly, if the "compress" program is available, you can use this
706 to write a ".tar.Z" file
707 use Archive::Tar;
709 use IO::File;
710 my $fh = IO::File->new( "| compress -c >$filename" );
712 my $tar = Archive::Tar->new();
713 ...
714 $tar->write($fh);
715 $fh->close ;
716 How do I handle Unicode strings?
718 "Archive::Tar" uses byte semantics for any files it reads from or
719 writes to disk. This is not a problem if you only deal with files
720 and never look at their content or work solely with byte strings.
721 But if you use Unicode strings with character semantics, some
722 additional steps need to be taken.
723 For example, if you add a Unicode string like
725 # Problem
727 $tar->add_data('file.txt', "Euro: \x{20AC}");
728 then there will be a problem later when the tarfile gets written
730 out to disk via "$tar->write()":
731 Wide character in print at .../Archive/Tar.pm line 1014.
733 The data was added as a Unicode string and when writing it out to
735 disk, the ":utf8" line discipline wasn't set by "Archive::Tar", so
736 Perl tried to convert the string to ISO-8859 and failed. The
737 written file now contains garbage.
738 For this reason, Unicode strings need to be converted to
740 UTF-8-encoded bytestrings before they are handed off to add_data():
741 use Encode;
743 my $data = "Accented character: \x{20AC}";
744 $data = encode('utf8', $data);
745 $tar->add_data('file.txt', $data);
747 A opposite problem occurs if you extract a UTF8-encoded file from a
749 tarball. Using get_content() on the "Archive::Tar::File" object
750 will return its content as a bytestring, not as a Unicode string.
751 If you want it to be a Unicode string (because you want character
753 semantics with operations like regular expression matching), you
754 need to decode the UTF8-encoded content and have Perl convert it
755 into a Unicode string:
756 use Encode;
758 my $data = $tar->get_content();
759 # Make it a Unicode string
761 $data = decode('utf8', $data);
762 There is no easy way to provide this functionality in
764 "Archive::Tar", because a tarball can contain many files, and each
765 of which could be encoded in a different way.
766
768 The AIX tar does not fill all unused space in the tar archive with
769 0x00. This sometimes leads to warning messages from "Archive::Tar".
770 Invalid header block at offset nnn
772 A fix for that problem is scheduled to be released in the following
774 levels of AIX, all of which should be coming out in the 4th quarter of
775 2009:
776 AIX 5.3 TL7 SP10
778 AIX 5.3 TL8 SP8
779 AIX 5.3 TL9 SP5
780 AIX 5.3 TL10 SP2
781 AIX 6.1 TL0 SP11
783 AIX 6.1 TL1 SP7
784 AIX 6.1 TL2 SP6
785 AIX 6.1 TL3 SP3
786 The IBM APAR number for this problem is IZ50240 (Reported component ID:
788 5765G0300 / AIX 5.3). It is possible to get an ifix for that problem.
789 If you need an ifix please contact your local IBM AIX support.
790
792 Check if passed in handles are open for read/write
793 Currently I don't know of any portable pure perl way to do this.
794 Suggestions welcome.
795 Allow archives to be passed in as string
797 Currently, we only allow opened filehandles or filenames, but not
798 strings. The internals would need some reworking to facilitate
799 stringified archives.
800 Facilitate processing an opened filehandle of a compressed archive
802 Currently, we only support this if the filehandle is an IO::Zlib
803 object. Environments, like apache, will present you with an opened
804 filehandle to an uploaded file, which might be a compressed
805 archive.
806
808 The GNU tar specification
809 <https://www.gnu.org/software/tar/manual/tar.html>
810 The PAX format specification
812 The specification which tar derives from;
813 <https://pubs.opengroup.org/onlinepubs/007904975/utilities/pax.html>
814
816 This module by Jos Boumans <kane@cpan.org>.
817 Please reports bugs to <bug-archive-tar@rt.cpan.org>.
819
821 Thanks to Sean Burke, Chris Nandor, Chip Salzenberg, Tim Heaney, Gisle
822 Aas, Rainer Tammer and especially Andrew Savige for their help and
823 suggestions.
824
826 This module is copyright (c) 2002 - 2009 Jos Boumans <kane@cpan.org>.
827 All rights reserved.
828 This library is free software; you may redistribute and/or modify it
830 under the same terms as Perl itself.
831perl v5.38.0 2023-07-20 Archive::Tar(3)