test if script called by cron
Hi, 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. thanks Paul. (anyone here going to EuroBSD con?) -- - Paul Macdonald IFDNRG Ltd Web and video hosting - t: 0131 5548070 m: 07970339546 e: p...@ifdnrg.com w: http://www.ifdnrg.com - IFDNRG 40 Maritime Street Edinburgh EH6 6SA High Specification Dedicated Servers from £100.00pm ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: test if script called by cron
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 ... You could also output the date command to that file to see when the script has been called: #!/bin/sh /bin/date +%Y-%m-%d %H:%M:%S /tmp/scriptrun # ... your script content here ... Of course you would have to manually remove that file after you have verified its existence and content. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: test if script called by cron
In the last episode (Sep 16), Paul Macdonald said: 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. You check to see if stdin is a terminal, but that's not conclusive. One way to know for sure is to look at the name of the process that launched you: if [ ! -t 0 ] ; then echo no tty, possibly run from cron fi parent=$(ps -o command= -p $PPID) case $parent in *cron* ) echo parent is $parent, almost certainly cron ;; esac -- Dan Nelson dnel...@allantgroup.com ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: test if script called by cron
On Mon, 16 Sep 2013 12:26:59 +0100 Paul Macdonald articulated: Hi, 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. thanks Paul. (anyone here going to EuroBSD con?) If you want to learn if the running script was called via cron, this would work, assuming you are running Bash. if [[ ! -t 0 ]]; then echo Running from Cron fi -- Jerry ♔ Disclaimer: off-list followups get on-list replies or get ignored. Please do not ignore the Reply-To header. __ ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
Re: test if script called by cron
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, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions-unsubscr...@freebsd.org
