What is the meaning of -a option in tar.exe command?
tar(1):
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-a, --auto-compress
(c mode only) Use the archive suffix to decide a set of the
format and the compressions. As a simple example,
tar -a -cf archive.tgz source.c source.h
creates a new archive with restricted pax format and gzip
compression,
tar -a -cf archive.tar.bz2.uu source.c source.h
creates a new archive with restricted pax format and bzip2
compression and uuencode compression,
tar -a -cf archive.zip source.c source.h
creates a new archive with zip format,
tar -a -jcf archive.tgz source.c source.h
ignores the "-j" option, and creates a new archive with
restricted pax format and gzip compression,
tar -a -jcf archive.xxx source.c source.h
if it is unknown suffix or no suffix, creates a new archive with
restricted pax format and bzip2 compression.
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