RTEMS 4.9.2 On-Line Library

Message Manager MESSAGE_QUEUE_GET_NUMBER_PENDING - Get number of messages pending on a queue

RTEMS C User's Guide

10.4.8: MESSAGE_QUEUE_GET_NUMBER_PENDING - Get number of messages pending on a queue

CALLING SEQUENCE:

rtems_status_code rtems_message_queue_get_number_pending(
  rtems_id  id,
  uint32_t *count
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL - number of messages pending returned successfully
RTEMS_INVALID_ADDRESS - count is NULL
RTEMS_INVALID_ID - invalid queue id

DESCRIPTION:

This directive returns the number of messages pending on this message queue in count. If no messages are present on the queue, count is set to zero.

NOTES:

Getting the number of pending messages on a global message queue which does not reside on the local node will generate a request to the remote node to actually obtain the pending message count for the specified message queue.

RTEMS C User's Guide