signed portBASE_TYPE xQueuePeekFromISR( xQueueHandle pxQueue, void * const pvBuffer )
{
signed portBASE_TYPE xReturn;
unsigned portBASE_TYPE uxSavedInterruptStatus;
signed char *pcOriginalReadPosition;

uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
{
/* We cannot block from an ISR, so check there is data available. */
if( pxQueue->uxMessagesWaiting > ( unsigned portBASE_TYPE ) 0 )
{
/* Remember the read position in case we are just peeking. */
pcOriginalReadPosition = pxQueue->pcReadFrom;

prvCopyDataFromQueue( pxQueue, pvBuffer );

/* The data is not being removed, so reset the read pointer to its
original position. */
pxQueue->pcReadFrom = pcOriginalReadPosition;
xReturn = pdPASS;
}
else
{
xReturn = pdFAIL;
}
}
portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );

return xReturn;
}