Text by encoding in Utf 8.
Represents whether the stream transaction was a success or a failure;
nothing is done by the library with the attached value. If you do not need
to send back a value to the caller of
withStream, you can use
Doesn't fail, but tells the client that all the data sent by the stream so far has been invalidated, and hence the queue of messages to be sent is cleared.
Opens a stream using the given handle and passes it to the function, and then unwraps the result given and gives any user data that the specific function wants to give back.