1BSDTAR(1) BSD General Commands Manual BSDTAR(1)
2
4 bsdtar — manipulate tape archives
5
7 bsdtar [bundled-flags ⟨args⟩] [⟨file⟩ | ⟨pattern⟩ ...]
8 bsdtar {-c} [options] [files | directories]
9 bsdtar {-r | -u} -f archive-file [options] [files | directories]
10 bsdtar {-t | -x} [options] [patterns]
11
13 bsdtar creates and manipulates streaming archive files. This implementa‐
14 tion can extract from tar, pax, cpio, zip, jar, ar, xar, rpm, 7-zip, and
15 ISO 9660 cdrom images and can create tar, pax, cpio, ar, zip, 7-zip, and
16 shar archives.
17 The first synopsis form shows a “bundled” option word. This usage is
19 provided for compatibility with historical implementations. See COMPATI‐
20 BILITY below for details.
21 The other synopsis forms show the preferred usage. The first option to
23 bsdtar is a mode indicator from the following list:
24 -c Create a new archive containing the specified items. The long
25 option form is --create.
26 -r Like -c, but new entries are appended to the archive. Note that
27 this only works on uncompressed archives stored in regular files.
28 The -f option is required. The long option form is --append.
29 -t List archive contents to stdout. The long option form is --list.
30 -u Like -r, but new entries are added only if they have a modifica‐
31 tion date newer than the corresponding entry in the archive.
32 Note that this only works on uncompressed archives stored in reg‐
33 ular files. The -f option is required. The long form is
34 --update.
35 -x Extract to disk from the archive. If a file with the same name
36 appears more than once in the archive, each copy will be ex‐
37 tracted, with later copies overwriting (replacing) earlier
38 copies. The long option form is --extract.
39 In -c, -r, or -u mode, each specified file or directory is added to the
41 archive in the order specified on the command line. By default, the con‐
42 tents of each directory are also archived.
43 In extract or list mode, the entire command line is read and parsed be‐
45 fore the archive is opened. The pathnames or patterns on the command
46 line indicate which items in the archive should be processed. Patterns
47 are shell-style globbing patterns as documented in tcsh(1).
48
50 Unless specifically stated otherwise, options are applicable in all oper‐
51 ating modes.
52 @archive
54 (c and r modes only) The specified archive is opened and the en‐
55 tries in it will be appended to the current archive. As a simple
56 example,
57 bsdtar -c -f - newfile @original.tar
58 writes a new archive to standard output containing a file newfile
59 and all of the entries from original.tar. In contrast,
60 bsdtar -c -f - newfile original.tar
61 creates a new archive with only two entries. Similarly,
62 bsdtar -czf - --format pax @-
63 reads an archive from standard input (whose format will be deter‐
64 mined automatically) and converts it into a gzip-compressed pax-
65 format archive on stdout. In this way, bsdtar can be used to
66 convert archives from one format to another.
67 -a, --auto-compress
69 (c mode only) Use the archive suffix to decide a set of the for‐
70 mat and the compressions. As a simple example,
71 bsdtar -a -cf archive.tgz source.c source.h
72 creates a new archive with restricted pax format and gzip com‐
73 pression,
74 bsdtar -a -cf archive.tar.bz2.uu source.c source.h
75 creates a new archive with restricted pax format and bzip2 com‐
76 pression and uuencode compression,
77 bsdtar -a -cf archive.zip source.c source.h
78 creates a new archive with zip format,
79 bsdtar -a -jcf archive.tgz source.c source.h
80 ignores the “-j” option, and creates a new archive with re‐
81 stricted pax format and gzip compression,
82 bsdtar -a -jcf archive.xxx source.c source.h
83 if it is unknown suffix or no suffix, creates a new archive with
84 restricted pax format and bzip2 compression.
85 --acls (c, r, u, x modes only) Archive or extract POSIX.1e or NFSv4
87 ACLs. This is the reverse of --no-acls and the default behavior
88 in c, r, and u modes (except on Mac OS X) or if bsdtar is run in
89 x mode as root. On Mac OS X this option translates extended ACLs
90 to NFSv4 ACLs. To store extended ACLs the --mac-metadata option
91 is preferred.
92 -B, --read-full-blocks
94 Ignored for compatibility with other tar(1) implementations.
95 -b blocksize, --block-size blocksize
97 Specify the block size, in 512-byte records, for tape drive I/O.
98 As a rule, this argument is only needed when reading from or
99 writing to tape drives, and usually not even then as the default
100 block size of 20 records (10240 bytes) is very common.
101 -C directory, --cd directory, --directory directory
103 In c and r mode, this changes the directory before adding the
104 following files. In x mode, change directories after opening the
105 archive but before extracting entries from the archive.
106 --chroot
108 (x mode only) chroot() to the current directory after processing
109 any -C options and before extracting any files.
110 --clear-nochange-fflags
112 (x mode only) Before removing file system objects to replace
113 them, clear platform-specific file attributes or file flags that
114 might prevent removal.
115 --exclude pattern
117 Do not process files or directories that match the specified pat‐
118 tern. Note that exclusions take precedence over patterns or
119 filenames specified on the command line.
120 --exclude-vcs
122 Do not process files or directories internally used by the ver‐
123 sion control systems ‘Arch’, ‘Bazaar’, ‘CVS’, ‘Darcs’,
124 ‘Mercurial’, ‘RCS’, ‘SCCS’, ‘SVN’ and ‘git’.
125 --fflags
127 (c, r, u, x modes only) Archive or extract platform-specific file
128 attributes or file flags. This is the reverse of --no-fflags and
129 the default behavior in c, r, and u modes or if bsdtar is run in
130 x mode as root.
131 --format format
133 (c, r, u mode only) Use the specified format for the created ar‐
134 chive. Supported formats include “cpio”, “pax”, “shar”, and
135 “ustar”. Other formats may also be supported; see
136 libarchive-formats(5) for more information about currently-sup‐
137 ported formats. In r and u modes, when extending an existing ar‐
138 chive, the format specified here must be compatible with the for‐
139 mat of the existing archive on disk.
140 -f file, --file file
142 Read the archive from or write the archive to the specified file.
143 The filename can be - for standard input or standard output. The
144 default varies by system; on FreeBSD, the default is /dev/sa0; on
145 Linux, the default is /dev/st0.
146 --gid id
148 Use the provided group id number. On extract, this overrides the
149 group id in the archive; the group name in the archive will be
150 ignored. On create, this overrides the group id read from disk;
151 if --gname is not also specified, the group name will be set to
152 match the group id.
153 --gname name
155 Use the provided group name. On extract, this overrides the
156 group name in the archive; if the provided group name does not
157 exist on the system, the group id (from the archive or from the
158 --gid option) will be used instead. On create, this sets the
159 group name that will be stored in the archive; the name will not
160 be verified against the system group database.
161 -H (c and r modes only) Symbolic links named on the command line
163 will be followed; the target of the link will be archived, not
164 the link itself.
165 -h (c and r modes only) Synonym for -L.
167 -I Synonym for -T.
169 --help Show usage.
171 --hfsCompression
173 (x mode only) Mac OS X specific (v10.6 or later). Compress ex‐
174 tracted regular files with HFS+ compression.
175 --ignore-zeros
177 An alias of --options read_concatenated_archives for compatibil‐
178 ity with GNU tar.
179 --include pattern
181 Process only files or directories that match the specified pat‐
182 tern. Note that exclusions specified with --exclude take prece‐
183 dence over inclusions. If no inclusions are explicitly speci‐
184 fied, all entries are processed by default. The --include option
185 is especially useful when filtering archives. For example, the
186 command
187 bsdtar -c -f new.tar --include='*foo*' @old.tgz
188 creates a new archive new.tar containing only the entries from
189 old.tgz containing the string ‘foo’.
190 -J, --xz
192 (c mode only) Compress the resulting archive with xz(1). In ex‐
193 tract or list modes, this option is ignored. Note that this tar
194 implementation recognizes XZ compression automatically when read‐
195 ing archives.
196 -j, --bzip, --bzip2, --bunzip2
198 (c mode only) Compress the resulting archive with bzip2(1). In
199 extract or list modes, this option is ignored. Note that this
200 tar implementation recognizes bzip2 compression automatically
201 when reading archives.
202 -k, --keep-old-files
204 (x mode only) Do not overwrite existing files. In particular, if
205 a file appears more than once in an archive, later copies will
206 not overwrite earlier copies.
207 --keep-newer-files
209 (x mode only) Do not overwrite existing files that are newer than
210 the versions appearing in the archive being extracted.
211 -L, --dereference
213 (c and r modes only) All symbolic links will be followed. Nor‐
214 mally, symbolic links are archived as such. With this option,
215 the target of the link will be archived instead.
216 -l, --check-links
218 (c and r modes only) Issue a warning message unless all links to
219 each file are archived.
220 --lrzip
222 (c mode only) Compress the resulting archive with lrzip(1). In
223 extract or list modes, this option is ignored. Note that this
224 tar implementation recognizes lrzip compression automatically
225 when reading archives.
226 --lz4 (c mode only) Compress the archive with lz4-compatible compres‐
228 sion before writing it. In extract or list modes, this option is
229 ignored. Note that this tar implementation recognizes lz4 com‐
230 pression automatically when reading archives.
231 --zstd (c mode only) Compress the archive with zstd-compatible compres‐
233 sion before writing it. In extract or list modes, this option is
234 ignored. Note that this tar implementation recognizes zstd com‐
235 pression automatically when reading archives.
236 --lzma (c mode only) Compress the resulting archive with the original
238 LZMA algorithm. In extract or list modes, this option is ig‐
239 nored. Use of this option is discouraged and new archives should
240 be created with --xz instead. Note that this tar implementation
241 recognizes LZMA compression automatically when reading archives.
242 --lzop (c mode only) Compress the resulting archive with lzop(1). In
244 extract or list modes, this option is ignored. Note that this
245 tar implementation recognizes LZO compression automatically when
246 reading archives.
247 -m, --modification-time
249 (x mode only) Do not extract modification time. By default, the
250 modification time is set to the time stored in the archive.
251 --mac-metadata
253 (c, r, u and x mode only) Mac OS X specific. Archive or extract
254 extended ACLs and extended file attributes using copyfile(3) in
255 AppleDouble format. This is the reverse of --no-mac-metadata.
256 and the default behavior in c, r, and u modes or if bsdtar is run
257 in x mode as root.
258 -n, --norecurse, --no-recursion
260 Do not operate recursively on the content of directories.
261 --newer date
263 (c, r, u modes only) Only include files and directories newer
264 than the specified date. This compares ctime entries.
265 --newer-mtime date
267 (c, r, u modes only) Like --newer, except it compares mtime en‐
268 tries instead of ctime entries.
269 --newer-than file
271 (c, r, u modes only) Only include files and directories newer
272 than the specified file. This compares ctime entries.
273 --newer-mtime-than file
275 (c, r, u modes only) Like --newer-than, except it compares mtime
276 entries instead of ctime entries.
277 --nodump
279 (c and r modes only) Honor the nodump file flag by skipping this
280 file.
281 --nopreserveHFSCompression
283 (x mode only) Mac OS X specific (v10.6 or later). Do not compress
284 extracted regular files which were compressed with HFS+ compres‐
285 sion before archived. By default, compress the regular files
286 again with HFS+ compression.
287 --null (use with -I or -T) Filenames or patterns are separated by null
289 characters, not by newlines. This is often used to read file‐
290 names output by the -print0 option to find(1).
291 --no-acls
293 (c, r, u, x modes only) Do not archive or extract POSIX.1e or
294 NFSv4 ACLs. This is the reverse of --acls and the default behav‐
295 ior if bsdtar is run as non-root in x mode (on Mac OS X as any
296 user in c, r, u and x modes).
297 --no-fflags
299 (c, r, u, x modes only) Do not archive or extract file attributes
300 or file flags. This is the reverse of --fflags and the default
301 behavior if bsdtar is run as non-root in x mode.
302 --no-mac-metadata
304 (x mode only) Mac OS X specific. Do not archive or extract ACLs
305 and extended file attributes using copyfile(3) in AppleDouble
306 format. This is the reverse of --mac-metadata. and the default
307 behavior if bsdtar is run as non-root in x mode.
308 --no-read-sparse
310 (c, r, u modes only) Do not read sparse file information from
311 disk. This is the reverse of --read-sparse.
312 --no-safe-writes
314 (x mode only) Do not create temporary files and use rename(2) to
315 replace the original ones. This is the reverse of --safe-writes.
316 --no-same-owner
318 (x mode only) Do not extract owner and group IDs. This is the
319 reverse of --same-owner and the default behavior if bsdtar is run
320 as non-root.
321 --no-same-permissions
323 (x mode only) Do not extract full permissions (SGID, SUID, sticky
324 bit, file attributes or file flags, extended file attributes and
325 ACLs). This is the reverse of -p and the default behavior if
326 bsdtar is run as non-root.
327 --no-xattrs
329 (c, r, u, x modes only) Do not archive or extract extended file
330 attributes. This is the reverse of --xattrs and the default be‐
331 havior if bsdtar is run as non-root in x mode.
332 --numeric-owner
334 This is equivalent to --uname "" --gname "". On extract, it
335 causes user and group names in the archive to be ignored in favor
336 of the numeric user and group ids. On create, it causes user and
337 group names to not be stored in the archive.
338 -O, --to-stdout
340 (x, t modes only) In extract (-x) mode, files will be written to
341 standard out rather than being extracted to disk. In list (-t)
342 mode, the file listing will be written to stderr rather than the
343 usual stdout.
344 -o (x mode) Use the user and group of the user running the program
346 rather than those specified in the archive. Note that this has
347 no significance unless -p is specified, and the program is being
348 run by the root user. In this case, the file modes and flags
349 from the archive will be restored, but ACLs or owner information
350 in the archive will be discarded.
351 -o (c, r, u mode) A synonym for --format ustar
353 --older date
355 (c, r, u modes only) Only include files and directories older
356 than the specified date. This compares ctime entries.
357 --older-mtime date
359 (c, r, u modes only) Like --older, except it compares mtime en‐
360 tries instead of ctime entries.
361 --older-than file
363 (c, r, u modes only) Only include files and directories older
364 than the specified file. This compares ctime entries.
365 --older-mtime-than file
367 (c, r, u modes only) Like --older-than, except it compares mtime
368 entries instead of ctime entries.
369 --one-file-system
371 (c, r, and u modes) Do not cross mount points.
372 --options options
374 Select optional behaviors for particular modules. The argument
375 is a text string containing comma-separated keywords and values.
376 These are passed to the modules that handle particular formats to
377 control how those formats will behave. Each option has one of
378 the following forms:
379 key=value
380 The key will be set to the specified value in every mod‐
381 ule that supports it. Modules that do not support this
382 key will ignore it.
383 key The key will be enabled in every module that supports it.
384 This is equivalent to key=1.
385 !key The key will be disabled in every module that supports
386 it.
387 module:key=value, module:key, module:!key
388 As above, but the corresponding key and value will be
389 provided only to modules whose name matches module.
390 The complete list of supported modules and keys for create and
392 append modes is in archive_write_set_options(3) and for extract
393 and list modes in archive_read_set_options(3).
394 Examples of supported options:
396 iso9660:joliet
397 Support Joliet extensions. This is enabled by default,
398 use !joliet or iso9660:!joliet to disable.
399 iso9660:rockridge
400 Support Rock Ridge extensions. This is enabled by de‐
401 fault, use !rockridge or iso9660:!rockridge to disable.
402 gzip:compression-level
403 A decimal integer from 1 to 9 specifying the gzip com‐
404 pression level.
405 gzip:timestamp
406 Store timestamp. This is enabled by default, use
407 !timestamp or gzip:!timestamp to disable.
408 lrzip:compression=type
409 Use type as compression method. Supported values are
410 bzip2, gzip, lzo (ultra fast), and zpaq (best, extremely
411 slow).
412 lrzip:compression-level
413 A decimal integer from 1 to 9 specifying the lrzip com‐
414 pression level.
415 lz4:compression-level
416 A decimal integer from 1 to 9 specifying the lzop com‐
417 pression level.
418 lz4:stream-checksum
419 Enable stream checksum. This is by default, use
420 lz4:!stream-checksum to disable.
421 lz4:block-checksum
422 Enable block checksum (Disabled by default).
423 lz4:block-size
424 A decimal integer from 4 to 7 specifying the lz4 compres‐
425 sion block size (7 is set by default).
426 lz4:block-dependence
427 Use the previous block of the block being compressed for
428 a compression dictionary to improve compression ratio.
429 zstd:compression-level
430 A decimal integer specifying the zstd compression level.
431 Supported values depend on the library version, common
432 values are from 1 to 22.
433 zstd:threads
434 Specify the number of worker threads to use. Setting
435 threads to a special value 0 makes zstd(1) use as many
436 threads as there are CPU cores on the system.
437 lzop:compression-level
438 A decimal integer from 1 to 9 specifying the lzop com‐
439 pression level.
440 xz:compression-level
441 A decimal integer from 0 to 9 specifying the xz compres‐
442 sion level.
443 xz:threads
444 Specify the number of worker threads to use. Setting
445 threads to a special value 0 makes xz(1) use as many
446 threads as there are CPU cores on the system.
447 mtree:keyword
448 The mtree writer module allows you to specify which mtree
449 keywords will be included in the output. Supported key‐
450 words include: cksum, device, flags, gid, gname, indent,
451 link, md5, mode, nlink, rmd160, sha1, sha256, sha384,
452 sha512, size, time, uid, uname. The default is equiva‐
453 lent to: “device, flags, gid, gname, link, mode, nlink,
454 size, time, type, uid, uname”.
455 mtree:all
456 Enables all of the above keywords. You can also use
457 mtree:!all to disable all keywords.
458 mtree:use-set
459 Enable generation of /set lines in the output.
460 mtree:indent
461 Produce human-readable output by indenting options and
462 splitting lines to fit into 80 columns.
463 zip:compression=type
464 Use type as compression method. Supported values are
465 store (uncompressed) and deflate (gzip algorithm).
466 zip:encryption
467 Enable encryption using traditional zip encryption.
468 zip:encryption=type
469 Use type as encryption type. Supported values are
470 zipcrypt (traditional zip encryption), aes128 (WinZip
471 AES-128 encryption) and aes256 (WinZip AES-256 encryp‐
472 tion).
473 read_concatenated_archives
474 Ignore zeroed blocks in the archive, which occurs when
475 multiple tar archives have been concatenated together.
476 Without this option, only the contents of the first con‐
477 catenated archive would be read. This option is compara‐
478 ble to the -i, --ignore-zeros option of GNU tar.
479 If a provided option is not supported by any module, that is a
480 fatal error.
481 -P, --absolute-paths
483 Preserve pathnames. By default, absolute pathnames (those that
484 begin with a / character) have the leading slash removed both
485 when creating archives and extracting from them. Also, bsdtar
486 will refuse to extract archive entries whose pathnames contain ..
487 or whose target directory would be altered by a symlink. This
488 option suppresses these behaviors.
489 -p, --insecure, --preserve-permissions
491 (x mode only) Preserve file permissions. Attempt to restore the
492 full permissions, including file modes, file attributes or file
493 flags, extended file attributes and ACLs, if available, for each
494 item extracted from the archive. This is the reverse of
495 --no-same-permissions and the default if bsdtar is being run as
496 root. It can be partially overridden by also specifying
497 --no-acls, --no-fflags, --no-mac-metadata or --no-xattrs.
498 --passphrase passphrase
500 The passphrase is used to extract or create an encrypted archive.
501 Currently, zip is the only supported format that supports encryp‐
502 tion. You shouldn't use this option unless you realize how inse‐
503 cure use of this option is.
504 --posix
506 (c, r, u mode only) Synonym for --format pax
507 -q, --fast-read
509 (x and t mode only) Extract or list only the first archive entry
510 that matches each pattern or filename operand. Exit as soon as
511 each specified pattern or filename has been matched. By default,
512 the archive is always read to the very end, since there can be
513 multiple entries with the same name and, by convention, later en‐
514 tries overwrite earlier entries. This option is provided as a
515 performance optimization.
516 --read-sparse
518 (c, r, u modes only) Read sparse file information from disk.
519 This is the reverse of --no-read-sparse and the default behavior.
520 -S (x mode only) Extract files as sparse files. For every block on
522 disk, check first if it contains only NULL bytes and seek over it
523 otherwise. This works similar to the conv=sparse option of dd.
524 -s pattern
526 Modify file or archive member names according to pattern. The
527 pattern has the format /old/new/[ghHprRsS] where old is a basic
528 regular expression, new is the replacement string of the matched
529 part, and the optional trailing letters modify how the replace‐
530 ment is handled. If old is not matched, the pattern is skipped.
531 Within new, ~ is substituted with the match, \1 to \9 with the
532 content of the corresponding captured group. The optional trail‐
533 ing g specifies that matching should continue after the matched
534 part and stop on the first unmatched pattern. The optional
535 trailing s specifies that the pattern applies to the value of
536 symbolic links. The optional trailing p specifies that after a
537 successful substitution the original path name and the new path
538 name should be printed to standard error. Optional trailing H,
539 R, or S characters suppress substitutions for hardlink targets,
540 regular filenames, or symlink targets, respectively. Optional
541 trailing h, r, or s characters enable substitutions for hardlink
542 targets, regular filenames, or symlink targets, respectively.
543 The default is hrs which applies substitutions to all names. In
544 particular, it is never necessary to specify h, r, or s.
545 --safe-writes
547 (x mode only) Extract files atomically. By default bsdtar un‐
548 links the original file with the same name as the extracted file
549 (if it exists), and then creates it immediately under the same
550 name and writes to it. For a short period of time, applications
551 trying to access the file might not find it, or see incomplete
552 results. If --safe-writes is enabled, bsdtar first creates a
553 unique temporary file, then writes the new contents to the tempo‐
554 rary file, and finally renames the temporary file to its final
555 name atomically using rename(2). This guarantees that an appli‐
556 cation accessing the file, will either see the old contents or
557 the new contents at all times.
558 --same-owner
560 (x mode only) Extract owner and group IDs. This is the reverse
561 of --no-same-owner and the default behavior if bsdtar is run as
562 root.
563 --strip-components count
565 Remove the specified number of leading path elements. Pathnames
566 with fewer elements will be silently skipped. Note that the
567 pathname is edited after checking inclusion/exclusion patterns
568 but before security checks.
569 -T filename, --files-from filename
571 In x or t mode, bsdtar will read the list of names to be ex‐
572 tracted from filename. In c mode, bsdtar will read names to be
573 archived from filename. The special name “-C” on a line by it‐
574 self will cause the current directory to be changed to the direc‐
575 tory specified on the following line. Names are terminated by
576 newlines unless --null is specified. Note that --null also dis‐
577 ables the special handling of lines containing “-C”. Note: If
578 you are generating lists of files using find(1), you probably
579 want to use -n as well.
580 --totals
582 (c, r, u modes only) After archiving all files, print a summary
583 to stderr.
584 -U, --unlink, --unlink-first
586 (x mode only) Unlink files before creating them. This can be a
587 minor performance optimization if most files already exist, but
588 can make things slower if most files do not already exist. This
589 flag also causes bsdtar to remove intervening directory symlinks
590 instead of reporting an error. See the SECURITY section below
591 for more details.
592 --uid id
594 Use the provided user id number and ignore the user name from the
595 archive. On create, if --uname is not also specified, the user
596 name will be set to match the user id.
597 --uname name
599 Use the provided user name. On extract, this overrides the user
600 name in the archive; if the provided user name does not exist on
601 the system, it will be ignored and the user id (from the archive
602 or from the --uid option) will be used instead. On create, this
603 sets the user name that will be stored in the archive; the name
604 is not verified against the system user database.
605 --use-compress-program program
607 Pipe the input (in x or t mode) or the output (in c mode) through
608 program instead of using the builtin compression support.
609 -v, --verbose
611 Produce verbose output. In create and extract modes, bsdtar will
612 list each file name as it is read from or written to the archive.
613 In list mode, bsdtar will produce output similar to that of
614 ls(1). An additional -v option will also provide ls-like details
615 in create and extract mode.
616 --version
618 Print version of bsdtar and libarchive, and exit.
619 -w, --confirmation, --interactive
621 Ask for confirmation for every action.
622 -X filename, --exclude-from filename
624 Read a list of exclusion patterns from the specified file. See
625 --exclude for more information about the handling of exclusions.
626 --xattrs
628 (c, r, u, x modes only) Archive or extract extended file at‐
629 tributes. This is the reverse of --no-xattrs and the default be‐
630 havior in c, r, and u modes or if bsdtar is run in x mode as
631 root.
632 -y (c mode only) Compress the resulting archive with bzip2(1). In
634 extract or list modes, this option is ignored. Note that this
635 tar implementation recognizes bzip2 compression automatically
636 when reading archives.
637 -Z, --compress, --uncompress
639 (c mode only) Compress the resulting archive with compress(1).
640 In extract or list modes, this option is ignored. Note that this
641 tar implementation recognizes compress compression automatically
642 when reading archives.
643 -z, --gunzip, --gzip
645 (c mode only) Compress the resulting archive with gzip(1). In
646 extract or list modes, this option is ignored. Note that this
647 tar implementation recognizes gzip compression automatically when
648 reading archives.
649
651 The following environment variables affect the execution of bsdtar:
652 TAR_READER_OPTIONS
654 The default options for format readers and compression read‐
655 ers. The --options option overrides this.
656 TAR_WRITER_OPTIONS
658 The default options for format writers and compression writ‐
659 ers. The --options option overrides this.
660 LANG The locale to use. See environ(7) for more information.
662 TAPE The default device. The -f option overrides this. Please see
664 the description of the -f option above for more details.
665 TZ The timezone to use when displaying dates. See environ(7) for
667 more information.
668
670 The bsdtar utility exits 0 on success, and >0 if an error occurs.
671
673 The following creates a new archive called file.tar.gz that contains two
674 files source.c and source.h:
675 bsdtar -czf file.tar.gz source.c source.h
676 To view a detailed table of contents for this archive:
678 bsdtar -tvf file.tar.gz
679 To extract all entries from the archive on the default tape drive:
681 bsdtar -x
682 To examine the contents of an ISO 9660 cdrom image:
684 bsdtar -tf image.iso
685 To move file hierarchies, invoke bsdtar as
687 bsdtar -cf - -C srcdir . | bsdtar -xpf - -C destdir
688 or more traditionally
689 cd srcdir ; bsdtar -cf - . | (cd destdir ; bsdtar -xpf -)
690 In create mode, the list of files and directories to be archived can also
692 include directory change instructions of the form -Cfoo/baz and archive
693 inclusions of the form @archive-file. For example, the command line
694 bsdtar -c -f new.tar foo1 @old.tgz -C/tmp foo2
695 will create a new archive new.tar. bsdtar will read the file foo1 from
696 the current directory and add it to the output archive. It will then
697 read each entry from old.tgz and add those entries to the output archive.
698 Finally, it will switch to the /tmp directory and add foo2 to the output
699 archive.
700 An input file in mtree(5) format can be used to create an output archive
702 with arbitrary ownership, permissions, or names that differ from existing
703 data on disk:
704 $ cat input.mtree
706 #mtree
707 usr/bin uid=0 gid=0 mode=0755 type=dir
708 usr/bin/ls uid=0 gid=0 mode=0755 type=file content=myls
709 $ tar -cvf output.tar @input.mtree
710 The --newer and --newer-mtime switches accept a variety of common date
712 and time specifications, including “12 Mar 2005 7:14:29pm”, “2005-03-12
713 19:14”, “5 minutes ago”, and “19:14 PST May 1”.
714 The --options argument can be used to control various details of archive
716 generation or reading. For example, you can generate mtree output which
717 only contains type, time, and uid keywords:
718 bsdtar -cf file.tar --format=mtree --options='!all,type,time,uid'
719 dir
720 or you can set the compression level used by gzip or xz compression:
721 bsdtar -czf file.tar --options='compression-level=9'.
722 For more details, see the explanation of the archive_read_set_options()
723 and archive_write_set_options() API calls that are described in
724 archive_read(3) and archive_write(3).
725
727 The bundled-arguments format is supported for compatibility with historic
728 implementations. It consists of an initial word (with no leading - char‐
729 acter) in which each character indicates an option. Arguments follow as
730 separate words. The order of the arguments must match the order of the
731 corresponding characters in the bundled command word. For example,
732 bsdtar tbf 32 file.tar
733 specifies three flags t, b, and f. The b and f flags both require argu‐
734 ments, so there must be two additional items on the command line. The 32
735 is the argument to the b flag, and file.tar is the argument to the f
736 flag.
737 The mode options c, r, t, u, and x and the options b, f, l, m, o, v, and
739 w comply with SUSv2.
740 For maximum portability, scripts that invoke tar should use the bundled-
742 argument format above, should limit themselves to the c, t, and x modes,
743 and the b, f, m, v, and w options.
744 Additional long options are provided to improve compatibility with other
746 tar implementations.
747
749 Certain security issues are common to many archiving programs, including
750 bsdtar. In particular, carefully-crafted archives can request that
751 bsdtar extract files to locations outside of the target directory. This
752 can potentially be used to cause unwitting users to overwrite files they
753 did not intend to overwrite. If the archive is being extracted by the
754 superuser, any file on the system can potentially be overwritten. There
755 are three ways this can happen. Although bsdtar has mechanisms to pro‐
756 tect against each one, savvy users should be aware of the implications:
757 • Archive entries can have absolute pathnames. By default, bsdtar
759 removes the leading / character from filenames before restoring
760 them to guard against this problem.
761 • Archive entries can have pathnames that include .. components.
763 By default, bsdtar will not extract files containing .. compo‐
764 nents in their pathname.
765 • Archive entries can exploit symbolic links to restore files to
767 other directories. An archive can restore a symbolic link to an‐
768 other directory, then use that link to restore a file into that
769 directory. To guard against this, bsdtar checks each extracted
770 path for symlinks. If the final path element is a symlink, it
771 will be removed and replaced with the archive entry. If -U is
772 specified, any intermediate symlink will also be unconditionally
773 removed. If neither -U nor -P is specified, bsdtar will refuse
774 to extract the entry.
775 To protect yourself, you should be wary of any archives that come from
776 untrusted sources. You should examine the contents of an archive with
777 bsdtar -tf filename
778 before extraction. You should use the -k option to ensure that bsdtar
779 will not overwrite any existing files or the -U option to remove any pre-
780 existing files. You should generally not extract archives while running
781 with super-user privileges. Note that the -P option to bsdtar disables
782 the security checks above and allows you to extract an archive while pre‐
783 serving any absolute pathnames, .. components, or symlinks to other di‐
784 rectories.
785
787 bzip2(1), compress(1), cpio(1), gzip(1), mt(1), pax(1), shar(1), xz(1),
788 libarchive(3), libarchive-formats(5), tar(5)
789
791 There is no current POSIX standard for the tar command; it appeared in
792 ISO/IEC 9945-1:1996 (“POSIX.1”) but was dropped from IEEE Std 1003.1-2001
793 (“POSIX.1”). The options supported by this implementation were developed
794 by surveying a number of existing tar implementations as well as the old
795 POSIX specification for tar and the current POSIX specification for pax.
796 The ustar and pax interchange file formats are defined by IEEE Std
798 1003.1-2001 (“POSIX.1”) for the pax command.
799
801 A tar command appeared in Seventh Edition Unix, which was released in
802 January, 1979. There have been numerous other implementations, many of
803 which extended the file format. John Gilmore's pdtar public-domain im‐
804 plementation (circa November, 1987) was quite influential, and formed the
805 basis of GNU tar. GNU tar was included as the standard system tar in
806 FreeBSD beginning with FreeBSD 1.0.
807 This is a complete re-implementation based on the libarchive(3) library.
809 It was first released with FreeBSD 5.4 in May, 2005.
810
812 This program follows ISO/IEC 9945-1:1996 (“POSIX.1”) for the definition
813 of the -l option. Note that GNU tar prior to version 1.15 treated -l as
814 a synonym for the --one-file-system option.
815 The -C dir option may differ from historic implementations.
817 All archive output is written in correctly-sized blocks, even if the out‐
819 put is being compressed. Whether or not the last output block is padded
820 to a full block size varies depending on the format and the output de‐
821 vice. For tar and cpio formats, the last block of output is padded to a
822 full block size if the output is being written to standard output or to a
823 character or block device such as a tape drive. If the output is being
824 written to a regular file, the last block will not be padded. Many com‐
825 pressors, including gzip(1) and bzip2(1), complain about the null padding
826 when decompressing an archive created by bsdtar, although they still ex‐
827 tract it correctly.
828 The compression and decompression is implemented internally, so there may
830 be insignificant differences between the compressed output generated by
831 bsdtar -czf - file
832 and that generated by
833 bsdtar -cf - file | gzip
834 The default should be to read and write archives to the standard I/O
836 paths, but tradition (and POSIX) dictates otherwise.
837 The r and u modes require that the archive be uncompressed and located in
839 a regular file on disk. Other archives can be modified using c mode with
840 the @archive-file extension.
841 To archive a file called @foo or -foo you must specify it as ./@foo or
843 ./-foo, respectively.
844 In create mode, a leading ./ is always removed. A leading / is stripped
846 unless the -P option is specified.
847 There needs to be better support for file selection on both create and
849 extract.
850 There is not yet any support for multi-volume archives.
852 Converting between dissimilar archive formats (such as tar and cpio) us‐
854 ing the @- convention can cause hard link information to be lost. (This
855 is a consequence of the incompatible ways that different archive formats
856 store hardlink information.)
857BSD January 31, 2020 BSD