Re: Backing up a minix partition

[Christian Lynbech <lynbech@daimi.aau.dk>]

>>>>> "Richard" == Richard Huveneers <huveneer@math.ruu.nl> writes:

Richard> But what if gtar compresses each file individually? In this
Richard> case an error only damages one file again.  I've looked
Richard> around a bit on a SUN, and there is a program called "bar"
Richard> which does exactly that. The problem is that I can't find any
Richard> sources, or an equivalent program.

Another feature of this scheme, is that getting a list of the contents
of an archive is much faster. You do not have to decompress everything
to see whats inside.

Hacking directly on the gtar sources may be as easy as trying to port
some SUN specific program. Besides, the bar program properly is
something SUN owns (and wont give you sources for) and such a hacked
up version would not accept the same options as our ordinary tar
(i.e. gtar).

One could also go from scratch, which is not quite as difficult as it
sounds. The tar format is quite simple, and there are (if I recall
correctly) include files in the libraries defining it. The program in
question could be designed specificly for generating the backups. Then
gtar could be used for the extraction.

It could even generate an index file (to be placed first!), so that
one wouldn't have to search the entire archive to see if a particular
file is present. Or do incremental backups. Or have the compression
routines builtin (sources taken from the gzip sources). Or verify each
disk after it has been written. In fact, such a program could be
immensely usefull.


------------------------------------------------------------------------------
Christian Lynbech               | Hit the philistines three times over the 
office: R0.33 (phone: 3217)	| head with the Elisp reference manual.
email: lynbech@daimi.aau.dk	|        - petonic@hal.com (Michael A. Petonic)
------------------------------------------------------------------------------