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 value causes the call to wait for an event to arrive for up to the specified number of microseconds.

    • If a negative timeout value is specified, the call waits indefinitely until an event arrives.

• If the block is configured to use NvSciEventService:

  • A non-zero timeout value causes it to return an NvSciError_BadParameter error.

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.