private function run (string $command) : ?string
    {
        $result = \trim(\shell_exec($command) ?? "");

        return "" !== $result
            ? $result
            : null;
    }
private function run (string $command) : ?string
    {
        $result = \trim(\shell_exec($command) ?? "");

        return "" !== $result
            ? $result
            : null;
    }
private function run ( string $ command ) : ? string { $ result = \ trim ( \ shell_exec ( $ command ) ?? "" ) ; return "" !== $ result ? $ result : null ; }
Runs the given command

@param string $command
@return string|null
Runs the given command