Crontab: dangling hyphens

Question

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?

Answer 1

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.