Event Query
Events can be queried from each block:
NvSciError
NvSciStreamBlockEventQuery(
    NvSciStreamBlock const      block,
    int64_t const               timeoutUsec,
    NvSciStreamEventType *const eventType
)- If the block is not configured to use NvSciEventService:
- 
        - If no events are pending in the block's queue, a non-zero timeout causes it to wait the specified number of microseconds for an event to arrive. If a negative value is used, the call waits forever.
 
- If the block is configured to use NvSciEventService:
- 
        -  Non-zero timeout causes it to return an NvSciError_BadParametererror.
 
-  Non-zero timeout causes it to return an 
On success, a pending event is removed from the block's queue, the output parameter is filled
      with the type of the event, and NvSciError_Success is returned. If no event
      is available before the timeout period ends, an NvSciError_Timeout error is
      returned. 
After an event is queried from a block, certain NvSciStream APIs become operational on the
      block. Refer to the API Reference for NvSciStreamEventType for additionally
      information about the functions that become operational for each event type queried.