A pointer to the data being sent. To set both fields, use the bitwise OR operator. A positive number indicating the actual number of bytes sent or a negative number indicating an error code. You use the OTSnd function to send data to a remote peer. Before you use this function, you must establish a connection with the peer.
Some protocols use expedited data for control or attention messages.
To determine whether the endpoint supports this service, examine the etsdu field of the TEndpointInfo structure. A positive integer for the etsdu field indicates the maximum size in bytes of expedited data that you can send. If the endpoint is in synchronous blocking mode, the OTSnd function returns after it actually sends the data. If flow-control restrictions prevent its sending the data, it retries the operation until it is able to send it. You should wait for this event and then send the data again.