Unpacking gzipped Files
Many files in MGNet have
been compressed using the GNU utility gzip (gzip can be obtained by anonymous ftp from
many sites including ftp://prep.ai.mit.edu and ftp://gatekeeper.dec.com). In particular, the
command
gzip -9 example
results in a much smaller file example.gz with an
extension of .gz (or .tgz). Files with the extension .tgz are UNIX tar files that
have been gzipped.
The files can be unpacked
using the GNU utility gunzip or zcat. For example,
gunzip example.gz
results in a reconstructed file example.
Tar files are UNIX tape
archive files, an ancient, but venerable storage format developed in the early
1970's. Gzipped tar files have an extension of .tgz in MGNet. The files can
be unpacked using either the GNU tar utility (or a tar utility with the z option)
tar zxvf example.tgz
or using a combination of the GNU utilities gunzip or zcat (really only special cases
of gzip) and a tar utility. For example,
gunzip example.tgz
tar xvf example.tar
or
zcat example.tgz | tar xvf -
will unpack all of the files from example.tgz. I have assumed that you are using
either a UNIX or a Windows based system.
