On Mon, 16 Sep 2013 23:28:17 -0400, kpn...@pobox.com wrote: > On Mon, Sep 16, 2013 at 02:05:04PM +0200, Polytropon wrote: > > On Mon, 16 Sep 2013 12:26:59 +0100, Paul Macdonald wrote: > > > Is there a simple way of testing whether a given script was called via > > > cron, > > > > > > I'd rather find a solution that would work from within the script rather > > > than setting an environment variable in the crontab. > > > > I'd suggest the script creates a file (lock file or, > > much easier, just a simple normal file) at its beginning: > > > > #!/bin/sh > > /usr/bin/touch /tmp/scriptrun > > # ... your script content here ... > > Wouldn't the lockf command be better than touch? That way you get the > condition code telling you whether or not the script is already running.
Yes, it would probably be better in this case. This, in combination with the suggestion of "test-t 0" to check if the script has been interactively called or not, looks like a better solution. However, the intial question does not make fully sure (at least to me as a non-native speaker) if the intention is (a) to check _if_ the script has been run via cron, or (b) to check if the script has been run via _cron_. :-) > > Of course you would have to manually remove that file > > after you have verified its existence and content. > > If you use lockf as a drop-in replacement for touch then, yes, you'll > need to keep the lock file until removing it at the end of the script. Depends. Let's say the script is scheduled at 3:00 and will finish in about half an hour. The "evidence file" will only be visible from 3:00 to ca. 3:30, so removing the "evidence file" after the script has finished could lead to a false-negative result ("has not been run"). This is also true for the more simple solution using the touch command (no rm call at the end of the script). -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... _______________________________________________ firstname.lastname@example.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"