This commit is contained in:
Sergey Poznyakoff
2004-05-10 08:04:37 +00:00
parent ad63cd4904
commit ee3b833d37

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@@ -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.
@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...}
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
There are a few ways to get around this. @FIXME-xref{Multiple Members
@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...
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