keep track of your last line's match. If you'll wrap your regex in parenthesis like so  if (/(cache|disk-)/i), you can assign the match to a variable, like so  $lastmatch = $1;, then each pass through your loop, you then can  print "\n" if ($lastmatch ne $1 and "disk-" eq lc $1);

In reply to Re: regexp look behind? by raybies
in thread regexp look behind? by dbs

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