cvs commit: src/sbin/dump dump.8 dump.h main.c tape.c src/sbin/restore extern.h main.c restore.8 tape.c

[Brian F. Feldman]

"David O'Brien" <obrien at FreeBSD.org> wrote:
> On Mon, Apr 12, 2004 at 07:58:07PM -0700, Brian Feldman wrote:
> > green       2004/04/12 19:58:07 PDT
> > 
> >   FreeBSD src repository
> > 
> >   Modified files:
> >     sbin/dump            dump.8 dump.h main.c tape.c 
> >     sbin/restore         extern.h main.c restore.8 tape.c 
> >   Log:
> >   Add -P arguments for dump(8) and restore(8) which allow the user to
> >   use backup methods other than files and tapes.  The -P argument is
> >   a normal sh(1) pipeline with either $DUMP_VOLUME or $RESTORE_VOLUME
> >   defined in the environment, respectively.
> 
> Why do you need an option for this?  Can't you just use 'dump ... |' and
> '... | restore'?

You can do that if you want to just dump a single volume and manually split 
it, but if you want to actually dump actual dump volumes, you run into 
problems.  Your pipeline would be outside dump, so it would have no 
knowledge of when one volume ends and another begins.  There are plenty of 
inelegant solutions to that requiring twice the operator intervention, but I 
prefer this elegant solution.  It's not perfect, though: auto-sizing would 
require having the dump pipeline child knowing when reading from dump(8) 
would be causing an EOF on the media and shutting down before it reads that
block.

-- 
Brian Fundakowski Feldman                           \'[ FreeBSD ]''''''''''\
  <> green at FreeBSD.org                               \  The Power to Serve! \
 Opinions expressed are my own.                       \,,,,,,,,,,,,,,,,,,,,,,\