From: Sergey Poznyakoff Date: Wed, 17 Oct 2007 09:12:54 +0000 (+0000) Subject: Update X-Git-Url: https://git.dogcows.com/gitweb?p=chaz%2Ftar;a=commitdiff_plain;h=3725b5606f4087d817e8599c5a52fd32157524a6 Update --- diff --git a/ChangeLog b/ChangeLog index f878d1d..76ce641 100644 --- a/ChangeLog +++ b/ChangeLog @@ -9,6 +9,7 @@ * src/tar.c: New options --auto-compress (-a) and --lzma * THANKS: Add Lasse Collin and Jean-Pierre Demailly. * NEWS: Update + * doc/tar.texi: Update 2007-10-12 Paul Eggert diff --git a/doc/tar.texi b/doc/tar.texi index 419999a..8316fa4 100644 --- a/doc/tar.texi +++ b/doc/tar.texi @@ -2402,6 +2402,13 @@ a read-only loopback mount, or use the @samp{noatime} mount option available on some systems. However, mounting typically requires superuser privileges and can be a pain to manage. +@opsummary{auto-compress} +@item --auto-compress +@itemx -a + +During a @option{--create} operation, enables automatic compressed +format recognition based on the archive suffix. @xref{gzip}. + @opsummary{backup} @item --backup=@var{backup-type} @@ -2718,6 +2725,12 @@ backup, using @var{snapshot-file} to determine which files to backup. With other operations, informs @command{tar} that the archive is in incremental format. @xref{Incremental Dumps}. +@opsummary{lzma} +@item --lzma + +This option tells @command{tar} to read or write archives through +@command{lzma}. @xref{gzip}. + @opsummary{mode} @item --mode=@var{permissions} @@ -7941,18 +7954,20 @@ switch to @samp{posix}. @cindex Storing archives in compressed format @GNUTAR{} is able to create and read compressed archives. It supports -@command{gzip} and @command{bzip2} compression programs. For backward -compatibility, it also supports @command{compress} command, although -we strongly recommend against using it, since there is a patent -covering the algorithm it uses and you could be sued for patent -infringement merely by running @command{compress}! Besides, it is less -effective than @command{gzip} and @command{bzip2}. +@command{gzip}, @command{bzip2} and @command{lzma} compression +programs. For backward compatibility, it also supports +@command{compress} command, although we strongly recommend against +using it, since there is a patent covering the algorithm it uses and +you could be sued for patent infringement merely by running +@command{compress}! Besides, it is by far less effective than other +compression programs. Creating a compressed archive is simple: you just specify a @dfn{compression option} along with the usual archive creation commands. The compression option is @option{-z} (@option{--gzip}) to create a @command{gzip} compressed archive, @option{-j} -(@option{--bzip2}) to create a @command{bzip2} compressed archive, and +(@option{--bzip2}) to create a @command{bzip2} compressed archive, +@command{lzma} to create an @asis{LZMA} compressed archive and @option{-Z} (@option{--compress}) to use @command{compress} program. For example: @@ -7960,6 +7975,26 @@ For example: $ @kbd{tar cfz archive.tar.gz .} @end smallexample +You can also let @GNUTAR{} select the compression program basing on +the suffix of the archive file name. This is done using +@option{--auto-compress} (@option{-a}) command line option. For +example, the following invocation will use @command{bzip2} for +compression: + +@smallexample +$ @kbd{tar cfa archive.tar.bz2 .} +@end smallexample + +@noindent +whereas the following one will use @command{lzma}: + +@smallexample +$ @kbd{tar cfa archive.tar.lzma .} +@end smallexample + +For a complete list of file name suffixes recognized by @GNUTAR{}, +@ref{auto-compress}. + Reading compressed archive is even simpler: you don't need to specify any additional options as @GNUTAR{} recognizes its format automatically. Thus, the following commands will list and extract the @@ -8001,6 +8036,28 @@ compressed. The following table summarizes compression options used by @GNUTAR{}. @table @option +@anchor{auto-compress} +@opindex auto-compress +@item --auto-compress +@itemx -a +Select a compression program to use by the archive file name +suffix. The following suffixes are recognized: + +@multitable @columnfractions 0.3 0.6 +@headitem Suffix @tab Compression program +@item @samp{.gz} @tab @command{gzip} +@item @samp{.tgz} @tab @command{gzip} +@item @samp{.taz} @tab @command{gzip} +@item @samp{.Z} @tab @command{compress} +@item @samp{.taZ} @tab @command{compress} +@item @samp{.bz2} @tab @command{bzip2} +@item @samp{.tz2} @tab @command{bzip2} +@item @samp{.tbz2} @tab @command{bzip2} +@item @samp{.tbz} @tab @command{bzip2} +@item @samp{.lzma} @tab @command{lzma} +@item @samp{.tlz} @tab @command{lzma} +@end multitable + @opindex gzip @opindex ungzip @item -z @@ -8047,6 +8104,10 @@ So, there are pros and cons. We'll see! @itemx --bzip2 Filter the archive through @code{bzip2}. Otherwise like @option{--gzip}. +@opindex lzma +@item --lzma +Filter the archive through @command{lzma}. Otherwise like @option{--gzip}. + @opindex compress @opindex uncompress @item -Z