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commandlinefu.com is the place to record those command-line gems that you return to again and again.

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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
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Multi-line grep

Terminal - Multi-line grep
perl -ne 'BEGIN{undef $/}; print "$ARGV\t$.\t$1\n" if m/(first line.*\n.*second line)/mg'
2010-03-18 15:46:10
User: hfs
Functions: perl
7
Multi-line grep

Using perl you can search for patterns spanning several lines, a thing that grep can't do. Append the list of files to above command or pipe a file through it, just as with regular grep. If you add the 's' modifier to the regex, the dot '.' also matches line endings, useful if you don't known how many lines you need are between parts of your pattern. Change '*' to '*?' to make it greedy, that is match only as few characters as possible.

See also http://www.commandlinefu.com/commands/view/1764/display-a-block-of-text-with-awk to do a similar thing with awk.

Edit: The undef has to be put in a begin-block, or a match in the first line would not be found.

Alternatives

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Terminal - Alternatives

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What others think

rock on perlre

Comment by linuxrawkstar 336 weeks and 4 days ago

Your point of view

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