KernelinsideMessage buffers

Updated May 2025

xMessageBufferReset()

[RTOS Message Buffer API]

message_buffer.h

1BaseType_t xMessageBufferReset( MessageBufferHandle_t xMessageBuffer );

Resets a message buffer to its initial, empty, state. Any data that was in the message buffer is discarded. A message buffer can only be reset if there are no tasks blocked waiting to either send to or receive from the message buffer.

Use 

xMessageBufferReset()
to reset a message buffer from a task. Use 
xMessageBufferResetFromISR()
to reset a message buffer from an interrupt service routine (ISR).

Message buffer functionality is enabled by including the FreeRTOS/source/stream_buffer.c source file in the build (as message buffers use stream buffers).

Parameters:

  • xMessageBuffer

    The handle of the message buffer being reset.

Returns:

  • If the message buffer is reset then pdPASS is returned.

  • If there was a task blocked waiting to send to or read from the message buffer then the message buffer will not be reset and pdFAIL is returned.