mkdir

// Create folder if not exist
		$folderName = 'images/gallery';
		$config['upload_path'] = $folderName;
		if(!is_dir($folderName))
		{
			mkdir($folderName, 0777);
		}

mkdir Verzeichnisname

sudo mkdir /usr/local/sbin

what that dose is make a new file at /usr/local/sbin

<?php mkdir("MyFolder"); ?>