$user_id = getmyuid(); echo "Current user ID is: " . $user_id;
$username = get_current_user(); echo "Current user is: " . $username;
$is_super_user = posix_getuid() === 0; if ($is_super_user) { echo "Current user is a superuser!"; } else { echo "Current user is not a superuser."; }This code snippet uses the `posix_getuid()` function to retrieve the ID of the System User running the PHP script, and checks if it is equal to 0 (which indicates a superuser). In terms of package libraries, some relevant ones for working with the System User in PHP might include the `posix` extension, which provides a set of functions for working with POSIX-compatible systems (such as Linux), and the `pcntl` extension, which provides access to process control functions.