From: Sergey Poznyakoff Date: Mon, 10 May 2004 08:04:37 +0000 (+0000) Subject: Updated X-Git-Url: https://git.brokenzipper.com/gitweb?a=commitdiff_plain;h=ee3b833d371b0554d9cf7f89b16633a2985aaca0;p=chaz%2Ftar Updated --- diff --git a/doc/tar.texi b/doc/tar.texi index 0139bd9..065f4ee 100644 --- a/doc/tar.texi +++ b/doc/tar.texi @@ -3934,13 +3934,10 @@ is the @samp{--update} operation; you can use this to add newer versions of archive members to an existing archive. To learn how to do this with @samp{--update}, @pxref{update}.) -@FIXME{Explain in second paragraph whether you can get to the previous -version -- explain whole situation somewhat more clearly.} - If you use @value{op-append} to add a file that has the same name as an archive member to an archive containing that archive member, then the old member is not deleted. What does happen, however, is somewhat -complex. @command{tar} @emph{allows} you to have infinite numbers of files +complex. @command{tar} @emph{allows} you to have infinite number of files with the same name. Some operations treat these same-named members no differently than any other set of archive members: for example, if you view an archive with @value{op-list}, you will see all of those members @@ -3954,14 +3951,33 @@ other members would end up in the working directory. This is because in the archive; the most recently archived members will be extracted last. Additionally, an extracted member will @emph{replace} a file of the same name which existed in the directory already, and @command{tar} -will not prompt you about this. Thus, only the most recently archived +will not prompt you about this@footnote{Unless you give it +@option{--keep-old-files} option, or the disk copy is newer than the +the one in the archive and you invoke @command{tar} with +@option{--keep-newer-files} option}. Thus, only the most recently archived member will end up being extracted, as it will replace the one extracted before it, and so on. +There exists a special option that allows you to get around this +behavior and extract (or list) only a particular copy of the file. +This is @option{--occurrence} option. If you run @command{tar} with +this option, it will extract only the first copy of the file. You +may also give this option an argument specifying the number of +copy to be extracted. Thus, for example if the archive +@file{archive.tar} contained three copies of file @file{myfile}, then +the command + +@smallexample +tar --extract --file archive.tar --occurrence=2 myfile +@end smallexample + +@noindent +would extract only the second copy. @xref{Option Summary,---occurrence}, for the description of @value{op-occurrence} option. + @FIXME{ hag -- you might want to incorporate some of the above into the -MMwtSN node; not sure. i didn't know how to make it simpler...} +MMwtSN node; not sure. i didn't know how to make it simpler... -There are a few ways to get around this. @FIXME-xref{Multiple Members +There are a few ways to get around this. (maybe xref Multiple Members with the Same Name.} @cindex Members, replacing with other members @@ -4085,10 +4101,20 @@ The newest version of @file{blues} is now at the end of the archive (note the different creation dates and file sizes). If you extract the archive, the older version of the file @file{blues} will be replaced by the newer version. You can confirm this by extracting -the archive and running @samp{ls} on the directory. @xref{Writing}, -for more information. (@emph{Please note:} This is the case unless -you employ the @value{op-backup} option. @FIXME-ref{Multiple Members -with the Same Name}.) +the archive and running @samp{ls} on the directory. + +If you wish to extract the first occurrence of the file @file{blues} +from the archive, use @value{op-occurrence} option, as shown in +the following example: + +@smallexample +$ @kbd{tar --extract -vv --occurrence --file=collection.tar blues} +-rw-rw-rw- me user 21 1996-09-23 16:44 blues +@end smallexample + +@xref{Writing}, for more information on @value{op-extract} and +@xref{Option Summary, --occurrence}, for the description of +@value{op-occurrence} option. @node update @subsection Updating an Archive