RawReceivePort constructor
Opens a long-lived port for receiving messages.
A RawReceivePort is low level and does not work with Zones. It cannot be paused. The data-handler must be set before the first message is received, otherwise the message is lost.
If handler
is provided, it's set as the RawReceivePort.handler.
The optional debugName
parameter can be set to associate a name with
this port that can be displayed in tooling.
Implementation
external factory RawReceivePort([Function? handler, String debugName = '']);