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Appendix A
OSQDel()
OS_OBJ_QTY OSQDel (OS_Q
*p_q,
OS_OPT
opt,
OS_ERR *p_err)
File
Called from
Code enabled by
OS_Q.C
Task
OS_CFG_Q_EN and
OS_CFG_Q_DEL_EN
OSQDel() is used to delete a message queue. This function should be used with care since
multiple tasks may rely on the presence of the message queue. Generally speaking, before
deleting a message queue, first delete all the tasks that can access the message queue.
However, it is highly recommended that you do not delete kernel objects at run time.
Arguments
p_q
is a pointer to the message queue to delete.
opt
specifies whether to delete the queue only if there are no pending tasks
(OS_OPT_DEL_NO_PEND), or always delete the queue regardless of whether
tasks are pending or not (OS_OPT_DEL_ALWAYS). In this case, all pending task
are readied.
p_err
is a pointer to a variable that is used to hold an error code. The error code can
be one of the following:
OS_ERR_NONE
OS_ERR_DEL_ISR
OS_ERR_OBJ_PTR_NULL
OS_ERR_OBJ_TYPE
OS_ERR_OPT_INVALID
OS_ERR_TASK_WAITING
438
if the call is successful and the message
queue has been deleted.
if the user attempts to delete the message
queue from an ISR.
if passing a NULL pointer for p_q.
if p_q is not pointing to a queue.
if not specifying one of the two options
mentioned in the opt argument.
if one or more tasks are waiting for messages
at the message queue and it is specified to
only delete if no task is pending.