crontab: question about a special case of the dash character in the time field spec

Posted by mdpc on Server Fault See other posts from Server Fault or by mdpc
Published on 2010-06-16T17:59:33Z Indexed on 2010/06/16 18:03 UTC
Read the original article Hit count: 240

Filed under:

linux

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unix

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cron

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crontab

In the SuSE /etc/crontab the entry to run the cron.{hourly,daily,monthly,weekly} scripts is coded as:

-*/15 * * * * root test -x /usr/lib/cron/run-crons && /usr/lib/cron/run-crons >/dev/null 2>&1

Notice that the very first character of the specification is a dash character (-), and this is NOT a typo.

Can somebody explain what the time spec '-*/15' means?

BTW, the stuff seems to be running fine.

Thanks

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