is_client_error() WordPress Function

The is_client_error() function in WordPress is used to check whether a given HTTP status code is a client error. A client error is defined as a 4xx HTTP status code, which indicates an error that occurred on the client side.

is_client_error( $sc ) #

function is_client_error ($sc) {
	return $sc >= 400 && $sc < 500;
}