XAR(1) User Commands XAR(1)NAMExar - eXtensible ARchiver
SYNOPSISxar -[ctx][v] ...
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 ta‐
ble of content's rich meta-data.
FUNCTIONS
One of the following options must be used:
-c Creates an archive
-t Lists the contents of an archive
-x Extracts an archive
NOTE: all of the above require the use of the -f option (filename) as
this release of xar doesn't correctly handle pipes or sockets.
-f The filename to use for creation, listing or extraction. With
extraction, this can be a POSIX regular expression.
OPTIONS--compression
Specifies the compression type to use. Valid values: none,
gzip, bzip2, lzma. Default value: gzip
-C <path>
On extract, xar will chdir to the specified path before extract‐
ing 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-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 verifica‐
tion. Valid values: none, sha1, and md5. 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 multi‐
ple 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.
EXAMPLESxar-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 direc‐
tory
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/
AUTHORS
Rob Braun <bbraun AT synack DOT net>
Landon Fuller <landonf AT bikemonkey DOT org>
David Leimbach
Kevin Van Vechten
version 1.6 November 1, 2007 XAR(1)
