Filter a file using a regex pattern

gistfile1.php

<?php

// This script filters the specified file over the specified regex pattern
// Each line that matches will be included in the new file

$source = fopen(__DIR__.'/sourcefile.csv', 'r');
$target = fopen(__DIR__.'/targetfile.csv', 'w');

while($line = fgets($source))
{
    if(preg_match('#^pattern$#', $line) > 0)
    {
        fwrite($target, $line);
    }
}

?>