How can PHP be configured to allow directory creation in a parent directory outside the root directory of a specific domain?

To allow directory creation in a parent directory outside the root directory of a specific domain in PHP, you can use the `mkdir()` function along with specifying the full path to the directory where you want to create a new directory. Make sure that the parent directory has the necessary permissions set to allow the PHP script to create directories.

$parentDirectory = '/full/path/to/parent/directory';
$newDirectory = $parentDirectory . '/new_directory';

if (!file_exists($newDirectory)) {
    mkdir($newDirectory, 0777, true);
    echo "Directory created successfully!";
} else {
    echo "Directory already exists!";
}