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In crontab you can specify ranges using hyphens (e. g. "0-15").

But recently I've seen an entry like this:

-*/15 * * * * command

What does hyphen plus an asterisk mean in this entry?

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up vote 1 down vote accepted

Argh, looks like it's an extension. Should've read this man page until the end.

If the uid of the owner is 0 (root), he can put a "-" as first character of a crontab entry. This will prevent cron from writing a syslog message about this command getting executed.

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What version of cron? What distribution? – Dennis Williamson Feb 17 '10 at 5:49
@Dennis Williamson, ISC cron 4.1 – Alex B Feb 19 '10 at 3:43

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