How can one ensure that the system's default temporary directory is correctly configured and accessible for file uploads in PHP?

To ensure that the system's default temporary directory is correctly configured and accessible for file uploads in PHP, you can use the `upload_tmp_dir` directive in the php.ini file to specify the path to a writable directory where PHP can store uploaded files temporarily. This directory should have the necessary permissions for PHP to write to it.

// Set the temporary upload directory in php.ini
ini_set('upload_tmp_dir', '/path/to/temporary/directory');