Queue Management
[API]

Modules


Detailed Description


uxQueueMessagesWaiting

queue.h
UBaseType_t uxQueueMessagesWaiting( QueueHandle_t xQueue );

Return the number of messages stored in a queue.

Parameters:
xQueue   A handle to the queue being queried.
Returns:
The number of messages available in the queue.


uxQueueMessagesWaitingFromISR

queue.h
UBaseType_t uxQueueMessagesWaiting( QueueHandle_t xQueue );

A version of uxQueueMessagesWaiting() that can be called from an ISR. Return the number of messages stored in a queue.

Parameters:
xQueue   A handle to the queue being queried.
Returns:
The number of messages available in the queue.


uxQueueSpacesAvailable

queue.h
UBaseType_t uxQueueSpacesAvailable( QueueHandle_t xQueue );

Return the number of free spaces in a queue.

Parameters:
xQueue   A handle to the queue being queried.
Returns:
The number of free spaces available in the queue.


vQueueDelete

queue.h
void vQueueDelete( QueueHandle_t xQueue );

Delete a queue – freeing all the memory allocated for storing of items placed on the queue.

Parameters:
xQueue   A handle to the queue to be deleted.


xQueueReset

queue.h
BaseType_t xQueueReset( QueueHandle_t xQueue );

Resets a queue to its original empty state.

Parameters:
xQueue   The handle of the queue being reset
Returns:
Since FreeRTOS V7.2.0 xQueueReset() always returns pdPASS.


xQueueIsQueueEmptyFromISR

queue.h
BaseType_t xQueueIsQueueEmptyFromISR( const QueueHandle_t xQueue );

Queries a queue to determine if the queue is empty. This function should only be used in an ISR.

Parameters:
xQueue   The handle of the queue being queried
Returns:
pdFALSE if the queue is not empty, or any other value if the queue is empty.


xQueueIsQueueFullFromISR

queue.h
BaseType_t xQueueIsQueueFullFromISR( const QueueHandle_t xQueue );

Queries a queue to determine if the queue is full. This function should only be used in an ISR.

Parameters:
xQueue   The handle of the queue being queried
Returns:
pdFALSE if the queue is not full, or any other value if the queue is full.







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