On Wed, 2 Apr 2008, Matt McCutchen wrote:

On Mon, 2008-03-31 at 11:43 +0200, Dag Wieers wrote:
Looking for an easy way to prevent a repetitive rsync to be running
multiple times, I was wondering if it could be useful to have an option
like:

        --pidfile /some/path/rsync-mirror-org.pid

So that rsync can be run directly from cron without requiring a wrapper
script to do pidfile handling.

This way rsync on startup could check the pid-file, see if another rsync
is using this pid, and bail out with an error if it is. Otherwise clean up
the stale pidfile and continue.

I think this would be very useful to instruct mirrors how to configure it,
rather than providing some script that needs local customizations.

I'm not convinced that a pidfile is better implemented in rsync than in
a wrapper script, which could be distributed in support/ of the source
tree.  If you don't care about actually having the pid in the file, you
could use the flock(1) utility, which executes a command while holding a
flock(2) lock on a specified file:

flock --nonblock /some/path/rsync-mirror-org.lock rsync ...

If the process goes away, the lock will too, so no manual cleanup of
stale locks is needed.

The flock utility is great. I learn something new everyday :)

Thanks a lot !
--
--   dag wieers,  [EMAIL PROTECTED],  http://dag.wieers.com/   --
[Any errors in spelling, tact or fact are transmission errors]
--
To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync
Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html

Reply via email to