The input data looks kinda like this

___DATA___

path/to/some/file
path/to/some/other/file
path/to/SUBTSTRING/file #replace entire line if SUBSTRING is found
path/to/file

##</code><code>##


sub scanForSubstringReplaceLine{
	my($inputText, $subStringToScan, $lineReplacement) = @_;
	my $replacedText;

        $inputText =~ s/$subStringToScan/$lineReplacement/g;

	$replacedText = $inputText;
	return $replacedText;
}