The GNU format uses additional file types to describe new types of
files in an archive. These are listed below.
This represents a directory and a list of files created by the
--incremental (-G) option. The size field gives the total
size of the associated list of files. Each file name is preceded by
either a ‘Y’ (the file should be in this archive) or an ‘N’.
(The file is a directory, or is not stored in the archive.) Each file
name is terminated by a null. There is an additional null after the
last file name.
This represents a file continued from another volume of a multi-volume
archive created with the --multi-volume (-M) option. The original
type of the file is not given here. The size field gives the
maximum size of this piece of the file (assuming the volume does
not end before the file is written out). The offset field
gives the offset from the beginning of the file where this part of
the file begins. Thus size plus offset should equal
the original size of the file.
This flag indicates that we are dealing with a sparse file. Note
that archiving a sparse file requires special operations to find
holes in the file, which mark the positions of these holes, along
with the number of bytes of data to be found after the hole.
This file type is used to mark the volume header that was given with
the --label=archive-label (-V archive-label) option when the archive was created. The name
field contains the name given after the --label=archive-label (-V archive-label) option.
The size field is zero. Only the first file in each volume
of an archive should have this type.
You may have trouble reading a GNU format archive on a
non-GNU system if the options --incremental (-G),
--multi-volume (-M), --sparse (-S), or --label=archive-label (-V archive-label) were
used when writing the archive. In general, if tar does not
use the GNU-added fields of the header, other versions of
tar should be able to read the archive. Otherwise, the
tar program will give an error, the most likely one being a
Published under the terms of the GNU General Public License