[RndTbl] Grep supports Perl regexp! Who knew?

[Adam Thompson]

Command Line Magic (@climagic) tweeted at 11:58 AM on Wed, Jan 09, 2013:
grep -o -P "(?<=CRON\[)\d+" /var/log/syslog # GNU grep supports perl regex expressions. This gives only the PID on CRON lines in syslog.
(https://twitter.com/climagic/status/289068621362241537)

_Adam