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From: std-unix@ut-sally.UUCP
Newsgroups: comp.std.unix
Subject: Re: More tar/cpio
Message-ID: <8198@ut-sally.UUCP>
Date: Mon, 1-Jun-87 22:55:52 EDT
Article-I.D.: ut-sally.8198
Posted: Mon Jun  1 22:55:52 1987
Date-Received: Sat, 6-Jun-87 09:44:26 EDT
References: <8046@ut-sally.UUCP> <8018@ut-sally.UUCP> <8024@ut-sally.UUCP> <8128@ut-sally.UUCP> <8144@ut-sally.UUCP>
Sender: std-unix@ut-sally.UUCP
Reply-To: mark@cbpavo.mis.oh.att.com (Mark Horton)
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Approved: jsq@sally.utexas.edu (Moderator, John Quarterman)

From: mark@cbpavo.mis.oh.att.com (Mark Horton)

In article <8144@ut-sally.UUCP> gnu@hoptoad.UUCP (John Gilmore) writes:
>*	People like cpio's user interface better.
>
>*	Tar's format on the tape is more portable.

Personally, I feel exactly the opposite.

The cpio format is quite portable, as long as you're careful to use
the c option.  The advantage to cpio format is that the images created
are considerably smaller than tar's.  Also, cpio can save/restore entries
from /dev, making it useful for backups.

[ The format in POSIX 10.1 can also do this.  -mod ]

The user interface, on the other hand, of cpio is horrible, unless you
are trying to do an incremental backup.  Compare the following equivalent
commands:
	$ tar c .
	$ find . -print | cpio -oc > /dev/rmt8

	$ tar x .
	$ cpio -icd < /dev/rmt8

Not only do you need a find command with cpio, but you'd better
remember the c and d options, or you'll regret it later!

cpio is a big win for incremental backups, as long as they fit
on one reel of tape:
	$ find . -newer /etc/lastbackup -print | cpio -oc > /dev/rmt8
Of course, that's a pretty major "as long as", and there are lots
of special versions of cpio that understand multiple backup volumes
and streaming I/O and such things.

	Mark

Volume-Number: Volume 11, Number 44