From: jayh@ms.uky.edu (Jay Hofacker) Subject: Re: Use of zip instead of compress Date: Wed, 14 Oct 1992 22:31:39 GMT
ddj+@cs.cmu.edu (Doug DeJulio) writes:
>I've been using zoo as a compresser, because it gives much better
>compression ratios than compress does. However for archival, I tar
>files first and then zoo the tarfile. That's because all of the
>PC-based archivers I've seen do nothing to preserve the ownership and
>mode of the files in the archive. That's fine if it's a directory of
>source code, but if for example there's a shellscript, the script
>won't work anymore once you take it back out of the archive (because
>the executable bit was stripped off by the archiver). Similarly, if
>you back up your home directory and then unpack it, all of your mail
>files would suddenly be world-readable! For this reason I'll always
>use tar or some other Unix based archiver at the lowest level, and
>then some other compressor.
Info-ZIPs zip 1.9 and unzip 5.0 preserve all Unix permissions, including
storing symbolic links as links instead of files (-y option).
(hmm.. Do they store the suid/sgid permissions too?...)
One thing zip/unzip doesn't seem to do is store devices as major/minor
numbers instead of accessing the device. ie 'zip -9ry devices /dev' attempted
to compress all of memory via "/dev/mem" instead of making a backup of
all the devices. Is there a way around this?
-- Jay Hofacker Email: jayh@ms.uky.edu --- "Hailing frequencies closed sir."