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Combining Archives

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The `--concatenate' (`-A') or option causes tar to add the contents of several archives to an existing archive.

Name the archives to be catenated on the command line. (Nothing happens if you don't list any.) The members, and their member names, will be copied verbatim from those archives. If this causes multiple members to have the same name, it does not delete either; all the members with the same name coexist. For information on how this affects reading the archive,

FIXME: ref Multiple Members with the Same Name

You must use this option to concatenate archives. If you just combine them with cat, the result will not be a valid tar format archive.

This operation cannot be performed on some tape drives, unfortunately, due to deficiencies in the formats thoes tape drives use.

To append copies of an archive or archives to the end of another archive, use `--concatenate' (`-A'). The source and target archives must already exist and have been created using compatable format parameters (

FIXME: pxref Matching Format Parameters

tar will stop reading an archive if it encounters an end-of-archive marker. The cat utility does not remove end-of-archive markers, and is therefore unsuitable for concatenating archives. `--concatenate' (`-A') removes the end-of-archive marker from the target archive before each new archive is appended.

FIXME: xref ignore-zeros

You must specify the source archives using `--file=archive-name' (`-f archive-name') (

FIXME: pxref Archive
). If you do not specify the target archive , tar uses the value of the environment variable TAPE, or, if this has not been set, the default archive name.

The following example adds the contents of the archive `hail/hail/fredonia' to the archive `stooges' (both archives were created in examples above):

tar --catenate --file=stooges hail/hail/fredonia

If you need to retrieve files from an archive that was added to using the cat utility, use the `--ignore-zeros' (`-i') option (

FIXME: pxref Archive Reading Options

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