RP1210_SENDMESSAGE (): Notes

This function is called by the client application seeking to send a message to the databus to which it is connected.

In 2010, due to NON_BLOCKING_IO and BLOCKINGJO conversations, the nBlockOnSend  parameter will be ignored and NON_BLOCKING_IO will only be used by a VDAAPI. The problem with NONJ3LOCKINGJO and BLOCKINGJO in an RP1210_SendMessage  type of call with mixtures of blocking can be problematic, especially in a multi-threaded environment. If one application/client fills up the queue using NON_BLOCKING_IO, and then a second application (or client) uses BLOCKINGJO, there is a possibility that the second app/client will have to wait a long time before the API clears the queue of the first applications' messages. This can cause applications timeouts.