Question

I have a little problem, I wrote a program, server role, doing an infinite loop waiting for client requests.
But I would like this program to also return his pid.
Thus, I think I should use multithreading.
Here’s my main :

int main(int argc, char **argv) {

    int pid = (int) getpid();
    int port = 5555

    ServerSoap *servsoap;
    servsoap = new ServerSoap(port, false);
    servsoap->StartServer(); //Here starts the infinite loop

    return pid; //so it never executes this
}

If it was bash scripting I would add & to run it in background.
Shall I use pthread ? And how to do it please ?

Thanks.
eo

Answer 1

If you put the infinite loop in a separate thread, and then return from main it will kill the whole process including your new thread. One solution, keeping to threads, is to make a detached thread. A better solution is probably to create a new process:

int main()
{
    int pid = fork();
    if (pid == -1)
        perror("fork");
    else if (pid == 0)
    {
        ServerSoap serversoap(5555, false);
        serversoap.StartServer();
    }

    return pid;
}

Edit: Also note the limit to the return value from main as noted in the answer from ecatmur.