If you want to grep a file in Perl, you can read it into an array first: 
use strict;

open my $fh, "file.txt" or die "Error opening file.txt: $!";
my @lines = <$fh>;
my @matches = grep /pattern/, @lines;

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There's also the File::Grep module from CPAN which provides some easy-to-use file grepping functionality.

In reply to Re: Questions about Grep by friedo
in thread Questions about Grep by Anonymous Monk

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