src/System.php
function find($args)
    {
        if (!is_array($args)) {
            $args = preg_split('/\s+/', $args, -1, PREG_SPLIT_NO_EMPTY);
        }
        $dir = realpath(array_shift($args));
        if (!$dir) {
            return array();
        }
        $patterns = array();
        $depth = 0;
        $do_files = $do_dirs = true;
        $args_count = count($args);
        for ($i = 0; $i < $args_count; $i++) {
            switch ($args[$i]) {
                case '-type':
                    if (in_array($args[$i+1], array('d', 'f'))) {
                        if ($args[$i+1] == 'd') {
                            $do_files = false;
                        } else {
                            $do_dirs = false;
                        }
                    }
                    $i++;
                    break;
                case '-name':
                    $name = preg_quote($args[$i+1], '#');
                    // our magic characters ? and * have just been escaped,
                    // so now we change the escaped versions to PCRE operators
                    $name = strtr($name, array('\?' => '.', '\*' => '.*'));
                    $patterns[] = '('.$name.')';
                    $i++;
                    break;
                case '-maxdepth':
                    $depth = $args[$i+1];
                    break;
            }
        }
        $path = System::_dirToStruct($dir, $depth, 0, true);
        if ($do_files && $do_dirs) {
            $files = array_merge($path['files'], $path['dirs']);
        } elseif ($do_dirs) {
            $files = $path['dirs'];
        } else {
            $files = $path['files'];
        }
        if (count($patterns)) {
            $dsq = preg_quote(DIRECTORY_SEPARATOR, '#');
            $pattern = '#(^|'.$dsq.')'.implode('|', $patterns).'($|'.$dsq.')#';
            $ret = array();
            $files_count = count($files);
            for ($i = 0; $i < $files_count; $i++) {
                // only search in the part of the file below the current directory
                $filepart = basename($files[$i]);
                if (preg_match($pattern, $filepart)) {
                    $ret[] = $files[$i];
                }
            }
            return $ret;
        }
        return $files;
    }
function find($args)
    {
        if (!is_array($args)) {
            $args = preg_split('/\s+/', $args, -1, PREG_SPLIT_NO_EMPTY);
        }
        $dir = realpath(array_shift($args));
        if (!$dir) {
            return array();
        }
        $patterns = array();
        $depth = 0;
        $do_files = $do_dirs = true;
        $args_count = count($args);
        for ($i = 0; $i < $args_count; $i++) {
            switch ($args[$i]) {
                case '-type':
                    if (in_array($args[$i+1], array('d', 'f'))) {
                        if ($args[$i+1] == 'd') {
                            $do_files = false;
                        } else {
                            $do_dirs = false;
                        }
                    }
                    $i++;
                    break;
                case '-name':
                    $name = preg_quote($args[$i+1], '#');
                    // our magic characters ? and * have just been escaped,
                    // so now we change the escaped versions to PCRE operators
                    $name = strtr($name, array('\?' => '.', '\*' => '.*'));
                    $patterns[] = '('.$name.')';
                    $i++;
                    break;
                case '-maxdepth':
                    $depth = $args[$i+1];
                    break;
            }
        }
        $path = System::_dirToStruct($dir, $depth, 0, true);
        if ($do_files && $do_dirs) {
            $files = array_merge($path['files'], $path['dirs']);
        } elseif ($do_dirs) {
            $files = $path['dirs'];
        } else {
            $files = $path['files'];
        }
        if (count($patterns)) {
            $dsq = preg_quote(DIRECTORY_SEPARATOR, '#');
            $pattern = '#(^|'.$dsq.')'.implode('|', $patterns).'($|'.$dsq.')#';
            $ret = array();
            $files_count = count($files);
            for ($i = 0; $i < $files_count; $i++) {
                // only search in the part of the file below the current directory
                $filepart = basename($files[$i]);
                if (preg_match($pattern, $filepart)) {
                    $ret[] = $files[$i];
                }
            }
            return $ret;
        }
        return $files;
    }
The "find" command

Usage:

System::find($dir);
System::find("$dir -type d");
System::find("$dir -type f");
System::find("$dir -name *.php");
System::find("$dir -name *.php -name *.htm*");
System::find("$dir -maxdepth 1");

Params implmented:
$dir            -> Start the search at this directory
-type d         -> return only directories
-type f         -> return only files
-maxdepth <n>   -> max depth of recursion
-name <pattern> -> search pattern (bash style). Multiple -name param allowed

@param  mixed Either array or string with the command line
@return array Array of found files
@static