c++ - libircclient : Selective connection absolutely impossible to debug -

i'm not type post question, , more search why doesn't work first, time did could, , can't figure out wrong.

so here's thing:

i'm programming irc bot, , i'm using libircclient, small c library handle irc connections. it's working pretty great, job , kinda easy use, ...

i'm connecting 2 different servers, , i'm using custom networking loop, uses select function. on personal computer, there's no problem loop, , works great.

but (here's problem), on remote server, bot hosted, can connect 1 server not other.

i tried debug could. went examine sources of libircclient, see how worked, , put printfs could, , see comes from, don't understand why this.

so here's code server (the irc_session_t objects encapsulated, it's kinda easy understand. feel free ask more informations if want to):

// connect first session first.connect();  // connect osu! session second.connect();  // initialize sockets sets fd_set sockets, out_sockets;  // initialize sockets count int sockets_count;  // initialize timeout struct struct timeval timeout;  // set running true running = true;  // while server running (which means always) while (running) {     // first session has disconnected     if (!first.connected())         // reconnect         first.connect();      // second session has disconnected     if (!second.connected())         // reconnect         second.connect();      // reset timeout values     timeout.tv_sec = 1;     timeout.tv_usec = 0;      // reset sockets count     sockets_count = 0;      // reset sockets , out sockets     fd_zero(&sockets);     fd_zero(&out_sockets);      // add sessions descriptors     irc_add_select_descriptors(first.session(), &sockets, &out_sockets, &sockets_count);     irc_add_select_descriptors(second.session(), &sockets, &out_sockets, &sockets_count);      // select something. if went wrong     int available = select(sockets_count + 1, &sockets, &out_sockets, null, &timeout);      // error     if (available < 0)         // error         utils::throw_error("server", "run", "something went wrong when selecting socket");      // have socket     if (available > 0)     {         // if there wrong when processing first session         if (irc_process_select_descriptors(first.session(), &sockets, &out_sockets))             // error             utils::throw_error("server", "run", utils::string_format("error first session: %s", first.get_error()));          // if there wrong when processing second session         if (irc_process_select_descriptors(second.session(), &sockets, &out_sockets))             // error             utils::throw_error("server", "run", utils::string_format("error second session: %s", second.get_error()));     } 

the problem in code line:

irc_process_select_descriptors(second.session(), &sockets, &out_sockets) 

always return error the first time it's called, , 1 server. weird thing on windows computer, works perfectly, while on ubuntu server, doesn't want to, , can't understand why.

i did in-depth debug, , saw libircclient this:

if (session->state == libirc_state_connecting && fd_isset(session->sock, out_set)) 

and goes wrong. session state correctly set libirc_state_connecting, second thing, fd_isset(session->sock, out_set) return false. returns true first session, second session, never.

the 2 servers irc.twitch.tv:6667 , irc.ppy.sh:6667. servers correctly set, , server passwords correct too, since works fine on personal computer.

sorry long post.

thanks in advance !

alright, after hours of debug, got problem.

so when session connected, enter in libirc_state_connecting state, , when calling irc_process_select_descriptors, check this:

if (session->state == libirc_state_connecting && fd_isset(session->sock, out_set)) 

the problem select() alter sockets sets, , remove sets not relevant.

so if server didn't send messages before calling irc_process_select_descriptors, fd_isset return 0, because select() thought socket not relevant.

i fixed writing

if (session->state == libirc_state_connecting) {     if(!fd_isset(session->sock, out_set))         return 0;      ... } 

so make program wait until server has sent anything.

sorry not having checked !