Hello, Due to a bug in my application, the code tried to use sendfile() with zero size.
As I see, sendfile() will happily proceed, and it will block here: https://github.com/apache/nuttx/blob/master/net/tcp/tcp_sendfile.c#L523 Obviously, it will never manage to send any data (as the requested size is 0), and after the timeout expires, it will return EAGAIN. This seems a bit wrong to me. Why not return immediately, but instead wait for the (inevitable) timeout? Why not return a more meaningful error code, or maybe just 0? I couldn't find what the standards dictate for this edge case, so maybe the current behavior is correct. What do you think?
