xar - eXtensible ARchiver

Authors

       Rob Braun <bbraun AT synack DOT net>
       Landon Fuller <landonf AT bikemonkey DOT org>
       David Leimbach
       Kevin Van Vechten

version 1.8                                       June 4, 2015                                            XAR(1)

Bugs

       Doesn't currently work with pipes or streams.  Might be fixed in a future release.

       Probably one or two more somewhere in there. If you find one please report it to
       http://code.google.com/p/xar/

Deprecation Warning

xar  is  no  longer  under  active development by Apple. Clients of xar should pursue alternative archive
       formats.

Description

       The XAR project aims to provide an easily extensible archive format. Important design  decisions  include
       an  easily extensible XML table of contents (TOC) for random access to archived files, storing the TOC at
       the beginning of the archive to allow for efficient handling of streamed archives, the ability to  handle
       files of arbitrarily large sizes, the ability to choose independent encodings for individual files in the
       archive,  the  ability  to store checksums for individual files in both compressed and uncompressed form,
       and the ability to query the table of content's rich meta-data.

Examples

       xar -cf sample.xar /home/uid
              Create a xar archive of all files in /home/uid

       xar -tf sample.xar
              List the contents of the xar archive sample.xar

       xar -xf sample.xar
              Extract the contents of sample.xar to the current working directory

Functions

Oneofthefollowingoptionsmustbeused:

       -c     Creates an archive

       -t     Lists the contents of an archive

       -x     Extracts an archive

       NOTE:alloftheaboverequiretheuseofthe-foption(filename)asthisreleaseofxardoesn'tcorrectlyhandlepipesorsockets.

       -f     The filename to use for creation, listing or extraction.  With extraction, this  can  be  a  POSIX
              regular expression.

Name

       xar - eXtensible ARchiver

Options

--compression
Specifies the compression type to use. Valid values: none, gzip, bzip2, lzma (on some systems).
Default value: gzip

-C <path>
On extract, xar will chdir to the specified path before extracting the archive.

-a Synonym for --compression=lzma

-j Synonym for --compression=bzip2

-z Synonym for --compression=gzip

--compression-args=<arguments>
Specifies arguments to the compression engine selected. gzip, bzip2, and lzma all take a single
integer argument between 0 and 9 specifying the compression level to use.

--dump-toc=<filename>
Has xar dump the xml header into the specified file. "-" can be specified to mean stdout.

--dump-toc-cksum
Dumps the ToC checksum to stdout along with the algorithm of the ToC.

--dump-header
Has xar print out the xar binary header information to stdout.

--extract-subdoc=<name>
Extracts the specified subdocument to a document in cwd named <name>.xml

--list-subdocs
List the subdocuments in the xml header

--toc-cksum
Specifies the hashing algorithm to use for xml header verification. Valid values: md5 (on some
systems), sha1, sha256, and sha512. Default value: sha1

--file-cksum
Specifies the hashing algorithm to use for file content verification. Valid values: md5 (on some
systems), sha1, sha256, and sha512. Default value: sha1

-l On archival, stay on the local device.

-P On extract, set ownership based on uid/gid. If the uid/gid can be set on the extracted file,
setuid/setgid bits will also be preserved.

-p On extract, set ownership based on symbolic names, if possible. If the uid/gid can be set on the
extracted file, setuid/setgid bits will also be preserved.

-s <filename>
On extract, specifies the file to extract subdocuments to. On archival, specifies an xml file to
add as a subdocument.

-v Verbose output

--exclude
Specifies a POSIX regular expression of files to exclude from adding to the archive during
creation or from being extracted during extraction. This option can be specified multiple times.

--rsize
Specifies a size (in bytes) for the internal libxar read buffer while performing I/O.

--coalesce-heap
When multiple files in the archive are identical, only store one copy of the data in the heap.
This creates smaller archives, but the archives created are not streamable.

--link-same
When the data section of multiple files are identical, hardlink them within the archive.

--no-compress
Specifies a POSIX regular expression of files to archive, but not compress. The archived files
will be copied raw into the archive. This can be used to exclude already gzipped files from being
gzipped during the archival process.

--prop-include
Specifies a file property to be included in the archive. When this option is specified, only the
specified options will be included. Anything not specifically included with this option will be
omitted. This option can be used multiple times.

--prop-exclude
Specifies a file property to be excluded from the archive. When this option is specified, all
file properties will be included except the specified properties. This option can be used
multiple times.

--distribution
Creates an archive to only contain file properties safe for file distribution. Currently, only
name, type, mode, and data are preserved with this option.

--keep-existing
Does not overwrite existing files during extraction. Keeps any previously existing files while
extracting.

-k Synonym for --keep-existing.

--keep-setuid
When extracting without -p or -P options, xar will extract files as the uid/gid of the extracting
process. In this situation, xar will strip setuid/setgid bits from the extracted files for
security reasons. --keep-setuid will preserve the setuid/setgid bits even though the uid/gid of
the extracted file is not the same as the archived file.