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FreeRTOS website now available in Simplified Chinese
New FreeRTOS Long Term Support version now available.
FreeRTOS Extended Maintenance Program (EMP) registration now open.
FreeRTOS-Plus-TCP v3.0.0 released:
Featured FreeRTOS IoT Integrations:


[FreeRTOS-Plus-TCP API Reference]

BaseType_t FreeRTOS_outstanding( Socket_t xSocket );

Returns the number of bytes in a TCP socket's Tx stream that are yet to be transmitted.


xSocket   The socket being queried.


If the socket referenced by the xSocket parameter is not a TCP socket then -pdFREERTOS_ERRNO_EINVAL is returned.

If the socket referenced by the xSocket parameter does not yet have a Tx stream then 0 is returned (the Tx stream is not created until it is required).

In all other cases the returned value is the number of bytes that remain in the socket's Tx stream.

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