"php recursive directory path" Code Answer

Try to use RecursiveIteratorIterator in combination with RecursiveDirectoryIterator

$path = realpath('/path/you/want/to/search/in');

$objects = new RecursiveIteratorIterator(
               new RecursiveDirectoryIterator($path), 
               RecursiveIteratorIterator::SELF_FIRST);

foreach($objects as $name => $object){
    if($object->getFilename() === 'work.txt') {
        echo $object->getPathname();
    }
}

Additional reading:

• http://www.phpro.org/tutorials/Introduction-to-SPL.html