Cron - Any advanced options?

[mark]

Kurian Thayil wrote:
> Hi All,
> 
> I am using RHEL 5.2 Server and I have 3 cron jobs enabled and all are
> relating to RSYNC. Now, all of these scripts are run once in every 7 minutes
> all day. The problem occurs when the scripts doesn't finish to execute in 7
> minutes. This will result in starting execution of the same script again and
> this will malfunction the setup.
> 
> Is there an option in CRON, which always check if CRON has started the
> process and is already running? Cron should execute the script only if the
> the process isn't running already. Any hints on this?

Not that I know of. Sounds like you'll have to add code to the scripts to see
if it's still running, and sleep if it is; along the lines of

	while [ ( ps -ef | grep myscript -c ) > 1 ]; do
	    sleep 60
        done

(I'm sure I'd have to fiddle with the test, but I don't have time at the moment.)

	mark