lwIP pbuf_free() Function: Deallocating Network Data Buffers

The function 'pbuf_free(p)' is used to deallocate a pbuf structure in the lwIP network stack.

The 'pbuf' structure is a buffer structure used in lwIP to hold network data. It is used to store data received from the network or data to be sent over the network.

The 'pbuf_free(p)' function frees the memory allocated for the pbuf structure and any associated data buffers. It releases the resources held by the pbuf, making it available for reuse.

The 'p' parameter is a pointer to the pbuf structure to be freed.

After calling 'pbuf_free(p)', the pbuf structure and its associated data buffers should no longer be used, as the memory they occupied may be reused for other purposes.