/**
* Shortcut for printing to `STDERR`. The message and parameters are passed
* through `sprintf` before output.
*
* @param string $msg The message to output in `printf` format. With no string,
* a newline is printed.
* @param mixed ... Either scalar arguments or a single array argument.
* @return void
*/
function err($msg = '')
{
\cli\Streams::_call('err', func_get_args());
}