Cron – Escaping Double Quotes and Percent Signs (%)

cron

The following command works from prompt but not from crontab.

 grep abc  /var/log/messages | grep "`date '+%B %d'`" | mail -s"abc log of `hostname`" s.o+`hostname`@gmail.com

I need to add it to daily cron.

Best Answer

You have to escape the % signs. They have a special meaning in crontabs:

man (5) crontab:

Percent-signs (%) in the command, unless escaped with backslash (\), 
will be changed into newline characters, and all data after the 
first % will be sent to the command as standard input.

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Here's what I did, and it seems to work in this situation. At least, it shows me an error, whereas running from the command line as the user doesn't show the error.

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Best Answer

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