$ composer require herrera-io/file-locator=1.*

locate('file.ini', false); // find all named "file.ini"">

use Herrera\FileLocator\Locator\FileSystemLocator;

$locator = new FileSystemLocator('/path/to/dir');
$locator = new FileSystemLocator(array(
    '/path/to/dir1',
    '/path/to/dir2',
    '/path/to/dir3' // etc
));

$file = $locator->locate('file.ini'); // return the first "file.ini" found
$files = $locator->locate('file.ini', false); // find all named "file.ini"

use Herrera\FileLocator\Locator\LocatorInterface;

class MyLocator implements LocatorInterface
{
    public function locate($file, $first = true)
    {
        // do something to locate $file

        // if $first is true, return the first matching result
            // if nothing is found, return null

        // if $first is false, generate a list of found $file(s) and return it
            // if nothing is found, return an empty array
    }
}

locate('file.ini', false); // find all named "file.ini"">

use Herrera\FileLocator\Collection;
use Herrera\FileLocator\Locator\FileSystemLocator;
use My\Library\CustomLocator;

$locators = new Collection();
$locators->add(new FileSystemLocator('/path/to/dir'));
$locators->add(new CustomLocator());

$file = $locator->locate('file.ini'); // return the first "file.ini" found
$files = $locator->locate('file.ini', false); // find all named "file.ini"