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LibrariesinsideAPI reference

Updated Jun 2025

FreeRTOS_outstanding()

[FreeRTOS-Plus-TCP API Reference]

FreeRTOS_sockets.h

1BaseType_t FreeRTOS_outstanding( Socket_t xSocket );

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

Parameters:

  • xSocket

    The socket being queried.

Returns:

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.