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diff --git a/archivers/libarchive/files/doc/man/bsdtar.1 b/archivers/libarchive/files/doc/man/bsdtar.1 deleted file mode 100644 index bd9f6189829..00000000000 --- a/archivers/libarchive/files/doc/man/bsdtar.1 +++ /dev/null @@ -1,1024 +0,0 @@ -.TH BSDTAR 1 "Oct 12, 2009" "" -.SH NAME -.ad l -\fB\%tar\fP -\- manipulate tape archives -.SH SYNOPSIS -.ad l -.br -\fB\%tar\fP -[\fIbundled-flags\fP <args>] -[<\fIfile\fP> | <\fIpattern\fP> ...] -.br -\fB\%tar\fP -{\fB\-c\fP} -[\fIoptions\fP] -[\fIfiles\fP | \fIdirectories\fP] -.br -\fB\%tar\fP -{\fB\-r\fP | \fB\-u\fP} -\fB\-f\fP \fIarchive-file\fP -[\fIoptions\fP] -[\fIfiles\fP | \fIdirectories\fP] -.br -\fB\%tar\fP -{\fB\-t\fP | \fB\-x\fP} -[\fIoptions\fP] -[\fIpatterns\fP] -.SH DESCRIPTION -.ad l -\fB\%tar\fP -creates and manipulates streaming archive files. -This implementation can extract from tar, pax, cpio, zip, jar, ar, -and ISO 9660 cdrom images and can create tar, pax, cpio, ar, -and shar archives. -.PP -The first synopsis form shows a -``bundled'' -option word. -This usage is provided for compatibility with historical implementations. -See COMPATIBILITY below for details. -.PP -The other synopsis forms show the preferred usage. -The first option to -\fB\%tar\fP -is a mode indicator from the following list: -.RS 5 -.TP -\fB\-c\fP -Create a new archive containing the specified items. -.TP -\fB\-r\fP -Like -\fB\-c\fP, -but new entries are appended to the archive. -Note that this only works on uncompressed archives stored in regular files. -The -\fB\-f\fP -option is required. -.TP -\fB\-t\fP -List archive contents to stdout. -.TP -\fB\-u\fP -Like -\fB\-r\fP, -but new entries are added only if they have a modification date -newer than the corresponding entry in the archive. -Note that this only works on uncompressed archives stored in regular files. -The -\fB\-f\fP -option is required. -.TP -\fB\-x\fP -Extract to disk from the archive. -If a file with the same name appears more than once in the archive, -each copy will be extracted, with later copies overwriting (replacing) -earlier copies. -.RE -.PP -In -\fB\-c\fP, -\fB\-r\fP, -or -\fB\-u\fP -mode, each specified file or directory is added to the -archive in the order specified on the command line. -By default, the contents of each directory are also archived. -.PP -In extract or list mode, the entire command line -is read and parsed before the archive is opened. -The pathnames or patterns on the command line indicate -which items in the archive should be processed. -Patterns are shell-style globbing patterns as -documented in -\fBtcsh\fP(1). -.SH OPTIONS -.ad l -Unless specifically stated otherwise, options are applicable in -all operating modes. -.RS 5 -.TP -\fB@\fP \fIarchive\fP -(c and r mode only) -The specified archive is opened and the entries -in it will be appended to the current archive. -As a simple example, -.RS 4 -\fB\%tar\fP \fB\-c\fP \fB\-f\fP \fI-\fP \fInewfile\fP \fB@\fP \fIoriginal.tar\fP -.RE -writes a new archive to standard output containing a file -\fInewfile\fP -and all of the entries from -\fIoriginal.tar\fP. -In contrast, -.RS 4 -\fB\%tar\fP \fB\-c\fP \fB\-f\fP \fI-\fP \fInewfile\fP \fIoriginal.tar\fP -.RE -creates a new archive with only two entries. -Similarly, -.RS 4 -\fB\%tar\fP \fB\-czf\fP \fI-\fP \fB\--format\fP \fBpax\fP \fB@\fP \fI-\fP -.RE -reads an archive from standard input (whose format will be determined -automatically) and converts it into a gzip-compressed -pax-format archive on stdout. -In this way, -\fB\%tar\fP -can be used to convert archives from one format to another. -.TP -\fB\-b\fP \fIblocksize\fP -Specify the block size, in 512-byte records, for tape drive I/O. -As a rule, this argument is only needed when reading from or writing -to tape drives, and usually not even then as the default block size of -20 records (10240 bytes) is very common. -.TP -\fB\-C\fP \fIdirectory\fP -In c and r mode, this changes the directory before adding -the following files. -In x mode, change directories after opening the archive -but before extracting entries from the archive. -.TP -\fB\--check-links\fP -(c and r modes only) -Issue a warning message unless all links to each file are archived. -.TP -\fB\--chroot\fP -(x mode only) -\fB\%chroot\fP() -to the current directory after processing any -\fB\-C\fP -options and before extracting any files. -.TP -\fB\--exclude\fP \fIpattern\fP -Do not process files or directories that match the -specified pattern. -Note that exclusions take precedence over patterns or filenames -specified on the command line. -.TP -\fB\--format\fP \fIformat\fP -(c, r, u mode only) -Use the specified format for the created archive. -Supported formats include -``cpio'', -``pax'', -``shar'', -and -``ustar''. -Other formats may also be supported; see -\fBlibarchive-formats\fP(5) -for more information about currently-supported formats. -In r and u modes, when extending an existing archive, the format specified -here must be compatible with the format of the existing archive on disk. -.TP -\fB\-f\fP \fIfile\fP -Read the archive from or write the archive to the specified file. -The filename can be -\fI-\fP -for standard input or standard output. -If not specified, the default tape device will be used. -(On -FreeBSD, -the default tape device is -\fI/dev/sa0\fP.) -.TP -\fB\-H\fP -(c and r mode only) -Symbolic links named on the command line will be followed; the -target of the link will be archived, not the link itself. -.TP -\fB\-h\fP -(c and r mode only) -Synonym for -\fB\-L\fP. -.TP -\fB\-I\fP -Synonym for -\fB\-T\fP. -.TP -\fB\--include\fP \fIpattern\fP -Process only files or directories that match the specified pattern. -Note that exclusions specified with -\fB\--exclude\fP -take precedence over inclusions. -If no inclusions are explicitly specified, all entries are processed by -default. -The -\fB\--include\fP -option is especially useful when filtering archives. -For example, the command -.RS 4 -\fB\%tar\fP \fB\-c\fP \fB\-f\fP \fInew.tar\fP \fB\--include='*foo*'\fP \fB@\fP \fIold.tgz\fP -.RE -creates a new archive -\fInew.tar\fP -containing only the entries from -\fIold.tgz\fP -containing the string -Sq foo. -.TP -\fB\-j\fP -(c mode only) -Compress the resulting archive with -\fBbzip2\fP(1). -In extract or list modes, this option is ignored. -Note that, unlike other -\fB\%tar\fP -implementations, this implementation recognizes bzip2 compression -automatically when reading archives. -.TP -\fB\-k\fP -(x mode only) -Do not overwrite existing files. -In particular, if a file appears more than once in an archive, -later copies will not overwrite earlier copies. -.TP -\fB\--keep-newer-files\fP -(x mode only) -Do not overwrite existing files that are newer than the -versions appearing in the archive being extracted. -.TP -\fB\-L\fP -(c and r mode only) -All symbolic links will be followed. -Normally, symbolic links are archived as such. -With this option, the target of the link will be archived instead. -.TP -\fB\-l\fP -This is a synonym for the -\fB\--check-links\fP -option. -.TP -\fB\-m\fP -(x mode only) -Do not extract modification time. -By default, the modification time is set to the time stored in the archive. -.TP -\fB\-n\fP -(c, r, u modes only) -Do not recursively archive the contents of directories. -.TP -\fB\--newer\fP \fIdate\fP -(c, r, u modes only) -Only include files and directories newer than the specified date. -This compares ctime entries. -.TP -\fB\--newer-mtime\fP \fIdate\fP -(c, r, u modes only) -Like -\fB\--newer\fP, -except it compares mtime entries instead of ctime entries. -.TP -\fB\--newer-than\fP \fIfile\fP -(c, r, u modes only) -Only include files and directories newer than the specified file. -This compares ctime entries. -.TP -\fB\--newer-mtime-than\fP \fIfile\fP -(c, r, u modes only) -Like -\fB\--newer-than\fP, -except it compares mtime entries instead of ctime entries. -.TP -\fB\--nodump\fP -(c and r modes only) -Honor the nodump file flag by skipping this file. -.TP -\fB\--null\fP -(use with -\fB\-I\fP, -\fB\-T\fP, -or -\fB\-X\fP) -Filenames or patterns are separated by null characters, -not by newlines. -This is often used to read filenames output by the -\fB\-print0\fP -option to -\fBfind\fP(1). -.TP -\fB\--numeric-owner\fP -(x mode only) -Ignore symbolic user and group names when restoring archives to disk, -only numeric uid and gid values will be obeyed. -.TP -\fB\-O\fP -(x, t modes only) -In extract (-x) mode, files will be written to standard out rather than -being extracted to disk. -In list (-t) mode, the file listing will be written to stderr rather than -the usual stdout. -.TP -\fB\-o\fP -(x mode) -Use the user and group of the user running the program rather -than those specified in the archive. -Note that this has no significance unless -\fB\-p\fP -is specified, and the program is being run by the root user. -In this case, the file modes and flags from -the archive will be restored, but ACLs or owner information in -the archive will be discarded. -.TP -\fB\-o\fP -(c, r, u mode) -A synonym for -\fB\--format\fP \fIustar\fP -.TP -\fB\--one-file-system\fP -(c, r, and u modes) -Do not cross mount points. -.TP -\fB\--options\fP \fIoptions\fP -Select optional behaviors for particular modules. -The argument is a text string containing comma-separated -keywords and values. -These are passed to the modules that handle particular -formats to control how those formats will behave. -Each option has one of the following forms: -.RS 5 -.TP -\fIkey=value\fP -The key will be set to the specified value in every module that supports it. -Modules that do not support this key will ignore it. -.TP -\fIkey\fP -The key will be enabled in every module that supports it. -This is equivalent to -\fIkey\fP \fB=1\fP. -.TP -\fI!key\fP -The key will be disabled in every module that supports it. -.TP -\fImodule:key=value\fP, \fImodule:key\fP, \fImodule:!key\fP -As above, but the corresponding key and value will be provided -only to modules whose name matches -\fImodule\fP. -.RE -The currently supported modules and keys are: -.RS 5 -.TP -\fBiso9660:joliet\fP -Support Joliet extensions. -This is enabled by default, use -\fB!joliet\fP -or -\fBiso9660:!joliet\fP -to disable. -.TP -\fBiso9660:rockridge\fP -Support Rock Ridge extensions. -This is enabled by default, use -\fB!rockridge\fP -or -\fBiso9660:!rockridge\fP -to disable. -.TP -\fBgzip:compression-level\fP -A decimal integer from 0 to 9 specifying the gzip compression level. -.TP -\fBxz:compression-level\fP -A decimal integer from 0 to 9 specifying the xz compression level. -.TP -\fBmtree:\fP \fIkeyword\fP -The mtree writer module allows you to specify which mtree keywords -will be included in the output. -Supported keywords include: -\fBcksum\fP, \fBdevice\fP, \fBflags\fP, \fBgid\fP, \fBgname\fP, \fBindent\fP, -\fBlink\fP, \fBmd5\fP, \fBmode\fP, \fBnlink\fP, \fBrmd160\fP, \fBsha1\fP, \fBsha256\fP, -\fBsha384\fP, \fBsha512\fP, \fBsize\fP, \fBtime\fP, \fBuid\fP, \fBuname\fP. -The default is equivalent to: -``device, flags, gid, gname, link, mode, nlink, size, time, type, uid, uname''. -.TP -\fBmtree:all\fP -Enables all of the above keywords. -You can also use -\fBmtree:!all\fP -to disable all keywords. -.TP -\fBmtree:use-set\fP -Enable generation of -\fB/set\fP -lines in the output. -.TP -\fBmtree:indent\fP -Produce human-readable output by indenting options and splitting lines -to fit into 80 columns. -.TP -\fBzip:compression\fP=\fItype\fP -Use -\fItype\fP -as compression method. -Supported values are store (uncompressed) and deflate (gzip algorithm). -.RE -If a provided option is not supported by any module, that -is a fatal error. -.TP -\fB\-P\fP -Preserve pathnames. -By default, absolute pathnames (those that begin with a / -character) have the leading slash removed both when creating archives -and extracting from them. -Also, -\fB\%tar\fP -will refuse to extract archive entries whose pathnames contain -\fI\& ..\fP -or whose target directory would be altered by a symlink. -This option suppresses these behaviors. -.TP -\fB\-p\fP -(x mode only) -Preserve file permissions. -Attempt to restore the full permissions, including owner, file modes, file -flags and ACLs, if available, for each item extracted from the archive. -By default, newly-created files are owned by the user running -\fB\%tar\fP, -the file mode is restored for newly-created regular files, and -all other types of entries receive default permissions. -If -\fB\%tar\fP -is being run by root, the default is to restore the owner unless the -\fB\-o\fP -option is also specified. -.TP -\fB\-q\fP (\fB\--fast-read\fP) -(x and t mode only) -Extract or list only the first archive entry that matches each pattern -or filename operand. -Exit as soon as each specified pattern or filename has been matched. -By default, the archive is always read to the very end, since -there can be multiple entries with the same name and, by convention, -later entries overwrite earlier entries. -This option is provided as a performance optimization. -.TP -\fB\-S\fP -(x mode only) -Extract files as sparse files. -For every block on disk, check first if it contains only NULL bytes and seek -over it otherwise. -This works similiar to the conv=sparse option of dd. -.TP -\fB\--strip-components\fP \fIcount\fP -(x mode only) -Remove the specified number of leading path elements. -Pathnames with fewer elements will be silently skipped. -Note that the pathname is edited after checking inclusion/exclusion patterns -but before security checks. -.TP -\fB\-s\fP \fIpattern\fP -Modify file or archive member names according to -\fIpattern\fP. -The pattern has the format -\fI/old/new/\fP [gps] -where -\fIold\fP -is a basic regular expression, -\fInew\fP -is the replacement string of the matched part, -and the optional trailing letters modify -how the replacement is handled. -If -\fIold\fP -is not matched, the pattern is skipped. -Within -\fInew\fP, -~ is substituted with the match, \1 to \9 with the content of -the corresponding captured group. -The optional trailing g specifies that matching should continue -after the matched part and stopped on the first unmatched pattern. -The optional trailing s specifies that the pattern applies to the value -of symbolic links. -The optional trailing p specifies that after a successful substitution -the original path name and the new path name should be printed to -standard error. -.TP -\fB\-T\fP \fIfilename\fP -In x or t mode, -\fB\%tar\fP -will read the list of names to be extracted from -\fIfilename\fP. -In c mode, -\fB\%tar\fP -will read names to be archived from -\fIfilename\fP. -The special name -``-C'' -on a line by itself will cause the current directory to be changed to -the directory specified on the following line. -Names are terminated by newlines unless -\fB\--null\fP -is specified. -Note that -\fB\--null\fP -also disables the special handling of lines containing -``-C''. -.TP -\fB\-U\fP -(x mode only) -Unlink files before creating them. -Without this option, -\fB\%tar\fP -overwrites existing files, which preserves existing hardlinks. -With this option, existing hardlinks will be broken, as will any -symlink that would affect the location of an extracted file. -.TP -\fB\--use-compress-program\fP \fIprogram\fP -Pipe the input (in x or t mode) or the output (in c mode) through -\fIprogram\fP -instead of using the builtin compression support. -.TP -\fB\-v\fP -Produce verbose output. -In create and extract modes, -\fB\%tar\fP -will list each file name as it is read from or written to -the archive. -In list mode, -\fB\%tar\fP -will produce output similar to that of -\fBls\fP(1). -Additional -\fB\-v\fP -options will provide additional detail. -.TP -\fB\--version\fP -Print version of -\fB\%tar\fP -and -\fB\%libarchive\fP, -and exit. -.TP -\fB\-w\fP -Ask for confirmation for every action. -.TP -\fB\-X\fP \fIfilename\fP -Read a list of exclusion patterns from the specified file. -See -\fB\--exclude\fP -for more information about the handling of exclusions. -.TP -\fB\-y\fP -(c mode only) -Compress the resulting archive with -\fBbzip2\fP(1). -In extract or list modes, this option is ignored. -Note that, unlike other -\fB\%tar\fP -implementations, this implementation recognizes bzip2 compression -automatically when reading archives. -.TP -\fB\-z\fP -(c mode only) -Compress the resulting archive with -\fBgzip\fP(1). -In extract or list modes, this option is ignored. -Note that, unlike other -\fB\%tar\fP -implementations, this implementation recognizes gzip compression -automatically when reading archives. -.TP -\fB\-Z\fP -(c mode only) -Compress the resulting archive with -\fBcompress\fP(1). -In extract or list modes, this option is ignored. -Note that, unlike other -\fB\%tar\fP -implementations, this implementation recognizes compress compression -automatically when reading archives. -.RE -.SH ENVIRONMENT -.ad l -The following environment variables affect the execution of -\fB\%tar\fP: -.RS 5 -.TP -.B LANG -The locale to use. -See -\fBenviron\fP(7) -for more information. -.TP -.B TAPE -The default tape device. -The -\fB\-f\fP -option overrides this. -.TP -.B TZ -The timezone to use when displaying dates. -See -\fBenviron\fP(7) -for more information. -.RE -.SH FILES -.ad l -.RS 5 -.TP -.B /dev/sa0 -The default tape device, if not overridden by the -.IR TAPE -environment variable or the -\fB\-f\fP -option. -.RE -.SH EXIT STATUS -.ad l -The \fBtar\fP utility exits 0 on success, and >0 if an error occurs. -.SH EXAMPLES -.ad l -The following creates a new archive -called -\fIfile.tar.gz\fP -that contains two files -\fIsource.c\fP -and -\fIsource.h\fP: -.RS 4 -\fB\%tar\fP \fB\-czf\fP \fIfile.tar.gz\fP \fIsource.c\fP \fIsource.h\fP -.RE -.PP -To view a detailed table of contents for this -archive: -.RS 4 -\fB\%tar\fP \fB\-tvf\fP \fIfile.tar.gz\fP -.RE -.PP -To extract all entries from the archive on -the default tape drive: -.RS 4 -\fB\%tar\fP \fB\-x\fP -.RE -.PP -To examine the contents of an ISO 9660 cdrom image: -.RS 4 -\fB\%tar\fP \fB\-tf\fP \fIimage.iso\fP -.RE -.PP -To move file hierarchies, invoke -\fB\%tar\fP -as -.RS 4 -\fB\%tar\fP \fB\-cf\fP \fI-\fP \fB\-C\fP \fIsrcdir\\fP. | \fB\%tar\fP \fB\-xpf\fP \fI-\fP \fB\-C\fP \fIdestdir\fP -.RE -or more traditionally -.RS 4 -cd srcdir \&; \fB\%tar\fP \fB\-cf\fP \fI-\\fP. | (cd destdir \&; \fB\%tar\fP \fB\-xpf\fP \fI-\fP) -.RE -.PP -In create mode, the list of files and directories to be archived -can also include directory change instructions of the form -\fB-C\fP \fIfoo/baz\fP -and archive inclusions of the form -\fB@\fP \fIarchive-file\fP. -For example, the command line -.RS 4 -\fB\%tar\fP \fB\-c\fP \fB\-f\fP \fInew.tar\fP \fIfoo1\fP \fB@\fP \fIold.tgz\fP \fB-C\fP \fI/tmp\fP \fIfoo2\fP -.RE -will create a new archive -\fInew.tar\fP. -\fB\%tar\fP -will read the file -\fIfoo1\fP -from the current directory and add it to the output archive. -It will then read each entry from -\fIold.tgz\fP -and add those entries to the output archive. -Finally, it will switch to the -\fI/tmp\fP -directory and add -\fIfoo2\fP -to the output archive. -.PP -An input file in -\fBmtree\fP(5) -format can be used to create an output archive with arbitrary ownership, -permissions, or names that differ from existing data on disk: -.PP -.RS 4 -$ cat input.mtree -.RE -.RS 4 -#mtree -.RE -.RS 4 -usr/bin uid=0 gid=0 mode=0755 type=dir -.RE -.RS 4 -usr/bin/ls uid=0 gid=0 mode=0755 type=file content=myls -.RE -.RS 4 -$ tar -cvf output.tar @input.mtree -.RE -.PP -The -\fB\--newer\fP -and -\fB\--newer-mtime\fP -switches accept a variety of common date and time specifications, including -``12 Mar 2005 7:14:29pm'', -``2005-03-12 19:14'', -``5 minutes ago'', -and -``19:14 PST May 1''. -.PP -The -\fB\--options\fP -argument can be used to control various details of archive generation -or reading. -For example, you can generate mtree output which only contains -\fBtype\fP, \fBtime\fP, -and -\fBuid\fP -keywords: -.RS 4 -\fB\%tar\fP \fB\-cf\fP \fIfile.tar\fP \fB\--format=mtree\fP \fB\--options='!all,type,time,uid'\fP \fIdir\fP -.RE -or you can set the compression level used by gzip or xz compression: -.RS 4 -\fB\%tar\fP \fB\-czf\fP \fIfile.tar\fP \fB\--options='compression-level=9'\fP. -.RE -For more details, see the explanation of the -\fB\%archive_read_set_options\fP() -and -\fB\%archive_write_set_options\fP() -API calls that are described in -\fBarchive_read\fP(3) -and -\fBarchive_write\fP(3). -.SH COMPATIBILITY -.ad l -The bundled-arguments format is supported for compatibility -with historic implementations. -It consists of an initial word (with no leading - character) in which -each character indicates an option. -Arguments follow as separate words. -The order of the arguments must match the order -of the corresponding characters in the bundled command word. -For example, -.RS 4 -\fB\%tar\fP \fBtbf\fP 32 \fIfile.tar\fP -.RE -specifies three flags -\fBt\fP, -\fBb\fP, -and -\fBf\fP. -The -\fBb\fP -and -\fBf\fP -flags both require arguments, -so there must be two additional items -on the command line. -The -\fI32\fP -is the argument to the -\fBb\fP -flag, and -\fIfile.tar\fP -is the argument to the -\fBf\fP -flag. -.PP -The mode options c, r, t, u, and x and the options -b, f, l, m, o, v, and w comply with SUSv2. -.PP -For maximum portability, scripts that invoke -\fB\%tar\fP -should use the bundled-argument format above, should limit -themselves to the -\fBc\fP, -\fBt\fP, -and -\fBx\fP -modes, and the -\fBb\fP, -\fBf\fP, -\fBm\fP, -\fBv\fP, -and -\fBw\fP -options. -.PP -Additional long options are provided to improve compatibility with other -tar implementations. -.SH SECURITY -.ad l -Certain security issues are common to many archiving programs, including -\fB\%tar\fP. -In particular, carefully-crafted archives can request that -\fB\%tar\fP -extract files to locations outside of the target directory. -This can potentially be used to cause unwitting users to overwrite -files they did not intend to overwrite. -If the archive is being extracted by the superuser, any file -on the system can potentially be overwritten. -There are three ways this can happen. -Although -\fB\%tar\fP -has mechanisms to protect against each one, -savvy users should be aware of the implications: -.RS 5 -.IP \(bu -Archive entries can have absolute pathnames. -By default, -\fB\%tar\fP -removes the leading -\fI/\fP -character from filenames before restoring them to guard against this problem. -.IP \(bu -Archive entries can have pathnames that include -\fI\& ..\fP -components. -By default, -\fB\%tar\fP -will not extract files containing -\fI\& ..\fP -components in their pathname. -.IP \(bu -Archive entries can exploit symbolic links to restore -files to other directories. -An archive can restore a symbolic link to another directory, -then use that link to restore a file into that directory. -To guard against this, -\fB\%tar\fP -checks each extracted path for symlinks. -If the final path element is a symlink, it will be removed -and replaced with the archive entry. -If -\fB\-U\fP -is specified, any intermediate symlink will also be unconditionally removed. -If neither -\fB\-U\fP -nor -\fB\-P\fP -is specified, -\fB\%tar\fP -will refuse to extract the entry. -.RE -To protect yourself, you should be wary of any archives that -come from untrusted sources. -You should examine the contents of an archive with -.RS 4 -\fB\%tar\fP \fB\-tf\fP \fIfilename\fP -.RE -before extraction. -You should use the -\fB\-k\fP -option to ensure that -\fB\%tar\fP -will not overwrite any existing files or the -\fB\-U\fP -option to remove any pre-existing files. -You should generally not extract archives while running with super-user -privileges. -Note that the -\fB\-P\fP -option to -\fB\%tar\fP -disables the security checks above and allows you to extract -an archive while preserving any absolute pathnames, -\fI\& ..\fP -components, or symlinks to other directories. -.SH SEE ALSO -.ad l -\fBbzip2\fP(1), -\fBcompress\fP(1), -\fBcpio\fP(1), -\fBgzip\fP(1), -\fBmt\fP(1), -\fBpax\fP(1), -\fBshar\fP(1), -\fBlibarchive\fP(3), -\fBlibarchive-formats\fP(5), -\fBtar\fP(5) -.SH STANDARDS -.ad l -There is no current POSIX standard for the tar command; it appeared -in -ISO/IEC 9945-1:1996 (``POSIX.1'') -but was dropped from -IEEE Std 1003.1-2001 (``POSIX.1''). -The options used by this implementation were developed by surveying a -number of existing tar implementations as well as the old POSIX specification -for tar and the current POSIX specification for pax. -.PP -The ustar and pax interchange file formats are defined by -IEEE Std 1003.1-2001 (``POSIX.1'') -for the pax command. -.SH HISTORY -.ad l -A -\fB\%tar\fP -command appeared in Seventh Edition Unix, which was released in January, 1979. -There have been numerous other implementations, -many of which extended the file format. -John Gilmore's -\fB\%pdtar\fP -public-domain implementation (circa November, 1987) -was quite influential, and formed the basis of GNU tar. -GNU tar was included as the standard system tar -in -FreeBSD -beginning with -FreeBSD 1.0. -.PP -This is a complete re-implementation based on the -\fBlibarchive\fP(3) -library. -.SH BUGS -.ad l -This program follows -ISO/IEC 9945-1:1996 (``POSIX.1'') -for the definition of the -\fB\-l\fP -option. -Note that GNU tar prior to version 1.15 treated -\fB\-l\fP -as a synonym for the -\fB\--one-file-system\fP -option. -.PP -The -\fB\-C\fP \fIdir\fP -option may differ from historic implementations. -.PP -All archive output is written in correctly-sized blocks, even -if the output is being compressed. -Whether or not the last output block is padded to a full -block size varies depending on the format and the -output device. -For tar and cpio formats, the last block of output is padded -to a full block size if the output is being -written to standard output or to a character or block device such as -a tape drive. -If the output is being written to a regular file, the last block -will not be padded. -Many compressors, including -\fBgzip\fP(1) -and -\fBbzip2\fP(1), -complain about the null padding when decompressing an archive created by -\fB\%tar\fP, -although they still extract it correctly. -.PP -The compression and decompression is implemented internally, so -there may be insignificant differences between the compressed output -generated by -.RS 4 -\fB\%tar\fP \fB\-czf\fP \fI-\fP file -.RE -and that generated by -.RS 4 -\fB\%tar\fP \fB\-cf\fP \fI-\fP file | \fB\%gzip\fP -.RE -.PP -The default should be to read and write archives to the standard I/O paths, -but tradition (and POSIX) dictates otherwise. -.PP -The -\fBr\fP -and -\fBu\fP -modes require that the archive be uncompressed -and located in a regular file on disk. -Other archives can be modified using -\fBc\fP -mode with the -\fI@archive-file\fP -extension. -.PP -To archive a file called -\fI@foo\fP -or -\fI-foo\fP -you must specify it as -\fI\& ./@foo\fP -or -\fI\& ./-foo\fP, -respectively. -.PP -In create mode, a leading -\fI\& ./\fP -is always removed. -A leading -\fI/\fP -is stripped unless the -\fB\-P\fP -option is specified. -.PP -There needs to be better support for file selection on both create -and extract. -.PP -There is not yet any support for multi-volume archives or for archiving -sparse files. -.PP -Converting between dissimilar archive formats (such as tar and cpio) using the -\fB@\fP \fI-\fP -convention can cause hard link information to be lost. -(This is a consequence of the incompatible ways that different archive -formats store hardlink information.) -.PP -There are alternative long options for many of the short options that -are deliberately not documented. |