From "perldoc perlop":

Binary "!~" is just like "=~" except the return value is negated in th
+e
       logical sense.

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So - use your pattern, and negate the match.

Try this pattern: 

!~/(:?[\da-f]{2}:){5}[\da-f]{2}/

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or better, Regexp::Common::net provides built-in regex matching for mac addresses.

        Clarity: it's like that one thing that is not the other thing, except for when it is.

In reply to Re: remove lines that do not match search pattern by NetWallah
in thread remove lines that do not match search pattern by jasonwolf

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