One way to modify a file in-place is to use Tie::File. The following will replace all lines which have the string 'foo' with the line 'This is now bar': 
use strict;
use warnings;

use Tie::File;
tie my @array, 'Tie::File', 'file.txt' or die $!;
for (@array) {
    if (/foo/) {
        $_ = 'This is now bar';
    }
}
untie @array;

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In reply to Re: match a line and edit it by toolic
in thread match a line and edit it by Anonymous Monk

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