docs: function errnoException(err, syscall, address, port) {
  		var errname;
  		var message;
  		if ((typeof err === 'undefined' ? 'undefined' : _typeof(err)) == 'object') {
  			errname = errorCodes[err.number] || err.number;
  			message = syscall + ' ' + errname + ' ' + err.message;
  		} else {
  			errname = err;
  			message = syscall + ' ' + errname;
  		}
  		var e = new Error(message);
  		e.code = e.errno = errname;
  		e.syscall = syscall;
  		if (port) {
  			e.port = port;
  		}
  		if (address) {
  			e.address = address;
  		}
  		return e;
  	}