Mine

function defname($address,$nick) {
$filename = 'defname.txt';
$somecontent = $address.$nick." ";
$t = " ".file_get_contents($filename);
preg_match("/ $address(.*?) /i",$t,$v);
$somecontent .= " ".str_replace($address.$v[1],"",$t);
print_r($v);
if(touch($filename)) {
    if (!$handle = fopen($filename, 'w')) {
         return "Cannot open file ($filename)";
}
else {
    if (fwrite($handle, $somecontent) === FALSE) {
        return "Cannot write to file ($filename)";
}
else {
return "\x0314Success, added\x0307 $nick \x0314as your default nick";
fclose($handle);
}
}
}
}