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Old 11-08-2012, 03:59 PM   #1
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crontab syntax or...?

I'm trying to setup a crontab and I've never done this before but I've created a simple perl script and I'd like it to be run every minute.

I create a file cron.txt containing:
* * * * * /directories to script/perl > /dev/null 2>&1
(blank line here)
I then enter the command: crontab cron.txt
then I enter: crontab -l
no complaints everything seems fine however the perl script is not executing...I enter the same command myself "perl" and it does what it's supposed to do.

I'm attempting to do this on a UNIX solaris box, any insight is greatly appreciated, thanks.

Old 11-08-2012, 04:17 PM   #2
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How do you now it's not executing? Does the code below show the timestamp updating?
while ls -lu "/directories to script/perl"
sleep 30
Is the filename free of spaces as would be normal?

You don't know what's happening because of throwing away your error messages - enable these at least until you know it is working.

Are there differences in the environment between your interactive shell and cron that would affect whether it works?
Old 11-08-2012, 04:43 PM   #3
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I don't actually know that it isn't trying to execute, but the script begins by reading in a file and then deleting it and that is not happening so I know that it's not getting that far at least.

The file name is free of spaces it is and directories are as well.

I'll have to enable the error messages and see what it gives.

And I'm not sure how to tell if there are environment differences between the shell and cron but I will look into it.

Old 11-08-2012, 04:51 PM   #4
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Yes there are differences. cron has a limited environment and does not know the the path to the perl interpreter. Does your script have the perl shebang? (#!/usr/bin/perl) Its been awhile since I've played with solaris and do not remember its path. Make your script executable and then all you need in cron is:

/path/to/ > /dev/null 2>&1
Old 11-08-2012, 08:09 PM   #5
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Have you checked /var/log/cron to see if its being called?
As above, enable stdout+stderr to file
Normally if cron has a problem, it will email the job owner or root.


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