@value{VERSION}, @value{UPDATED}), which creates and extracts files
from archives.
-Copyright @copyright{} 1992, 1994, 1995, 1996, 1997, 1999, 2000, 2001,
-2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software
-Foundation, Inc.
+Copyright @copyright{} 1992, 1994--1997, 1999--2001, 2003--2013 Free
+Software Foundation, Inc.
@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
-any later version published by the Free Software Foundation; with no
-Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
-A copy of the license is included in the section entitled ``GNU Free
-Documentation License''.
+any later version published by the Free Software Foundation; with the
+Invariant Sections being ``GNU General Public License'', with the
+Front-Cover Texts being ``A GNU Manual'', and with the Back-Cover Texts
+as in (a) below. A copy of the license is included in the section
+entitled ``GNU Free Documentation License''.
+
+(a) The FSF's Back-Cover Text is: ``You have the freedom to
+copy and modify this GNU manual.''
@end quotation
@end copying
@item --ignore-failed-read
Do not exit unsuccessfully merely because an unreadable file was encountered.
-@xref{Reading}.
+@xref{Ignore Failed Read}.
@opsummary{ignore-zeros}
@item --ignore-zeros
@smallexample
tar (GNU tar) @value{VERSION}
-Copyright (C) 2011 Free Software Foundation, Inc.
-Copyright (C) 2011 Free Software Foundation, Inc.
+Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
such devices or remote files is reblocked by another copy of the
@command{tar} program to enforce the specified (or default) record
size. The default compression parameters are used. Most compression
-programs allow to override these by setting a program-specific
-environment variable. For example, when using @command{gzip} you can
-use @env{GZIP} as in the example below:
+programs let you override these by setting a program-specific
+environment variable. For example, with @command{gzip} you can set
+@env{GZIP}:
@smallexample
-$ @kbd{GZIP=--best tar czf archive.tar.gz subdir}
+$ @kbd{GZIP='-9 -n' tar czf archive.tar.gz subdir}
@end smallexample
@noindent
-Another way would be to use the @option{-I} option instead (see
-below), e.g.:
+The traditional way to do this is to use a pipe:
@smallexample
-$ @kbd{tar -cf archive.tar.gz -I 'gzip --best' subdir}
-@end smallexample
-
-@noindent
-Finally, the third, traditional, way to achieve the same result is to
-use pipe:
-
-@smallexample
-$ @kbd{tar cf - subdir | gzip --best -c - > archive.tar.gz}
+$ @kbd{tar cf - subdir | gzip -9 -n > archive.tar.gz}
@end smallexample
@cindex corrupted archives
-About corrupted compressed archives: compressed files have no
-redundancy, for maximum compression. The adaptive nature of the
+Compressed archives are easily corrupted, because compressed files
+have little redundancy. The adaptive nature of the
compression scheme means that the compression tables are implicitly
spread all over the archive. If you lose a few blocks, the dynamic
construction of the compression tables becomes unsynchronized, and there
is little chance that you could recover later in the archive.
-Another compression options provide a better control over creating
+Other compression options provide better control over creating
compressed archives. These are:
@table @option
Use external compression program @var{prog}. Use this option if you
are not happy with the compression program associated with the suffix
at compile time or if you have a compression program that @GNUTAR{}
-does not support. There are two requirements to which @var{prog}
-should comply:
+does not support. The program should follow two conventions:
-First, when called without options, it should read data from standard
+First, when invoked without options, it should read data from standard
input, compress it and output it on standard output.
-Secondly, if called with @option{-d} argument, it should do exactly
+Secondly, if invoked with the @option{-d} option, it should do exactly
the opposite, i.e., read the compressed data from the standard input
and produce uncompressed data on the standard output.
@end table
@command{rsh} or @command{remsh} to the remote machine, optionally
using a different login name if one is supplied.
-A copy of the source for the remote tape server is provided. It is
-Copyright @copyright{} 1983 by the Regents of the University of
-California, but can be freely distributed. It is compiled and
+A copy of the source for the remote tape server is provided. Its
+source code can be freely distributed. It is compiled and
installed by default.
@cindex absolute file names
@smallexample
@group
-#! /bin/sh
+#! /bin/bash
+# For this script it's advisable to use a shell, such as Bash,
+# that supports a TAR_FD value greater than 9.
+
echo Preparing volume $TAR_VOLUME of $TAR_ARCHIVE.
name=`expr $TAR_ARCHIVE : '\(.*\)-.*'`
projects / chaz / tar / blobdiff