org\bovigo\vfs\vfsStream::getCurrentGroup PHP Method

If the system does not support posix_getgid() the current group will be root (0).

public static getCurrentGroup ( ) : integer
return	integer

    public static function getCurrentGroup()
    {
        return function_exists('posix_getgid') ? posix_getgid() : self::GROUP_ROOT;
    }

vfsStream