Retrieving socket after binding to port 0

[michalwarda]

I'm trying to create a server with port 0 as the parameter to get a dynamically assigned port. The problem though is that I'm not sure how to retrieve the port then. Any suggestions?

And if it's important I'm using capi.

[uNetworkingAB]

https://github.com/uNetworking/uSockets/blob/5d1d640968fb9361575b8454605c1fdc119588c3/src/libusockets.h#L315

Ssl is 0 or 1

[uNetworkingAB]

It's actually not a C++ wrapper, it's a C wrapper. The native library is C++

[uNetworkingAB]

Ah okay I see. This particular function is C. There is no C++ wrapper for uSockets.

[0xmemorygrinder]

Alright I can use the C api but how do I get the struct us_socket_t * when using the c++ examples ?

[uNetworkingAB]

Okay I see. You can pass the listen socket us_listen_socket_t as us_socket_t. You get the listen socket from app.listen

[0xmemorygrinder]

Excellent thanks for your answer !

[ddevienne]

In case that helps anyone:

    inline constexpr bool wSSL = false;
    app.listen(
        port, [&ctx, port](us_listen_socket_t* socket) -> void {
            if (socket) {
                int actual_port = us_socket_local_port(wSSL? 1: 0, (us_socket_t*)socket);
                assert((!port && actual_port) || (port == actual_port));
                fmt::print(ctx.out(), "Serving over HTTP{} on port {}\n", wSSL? "S": "", actual_port);
            }
        }
    );

Which results in:

D:\>acme.exe
Serving over HTTP on port 8888
^C
D:\>acme.exe --port 0
Serving over HTTP on port 58196
^C
D:\>acme.exe --port 0
Serving over HTTP on port 58197