Why shutdown a socket can't let the select() return?

Question

In my program, there is a thread blocking on a listen socket, which waits for other connections, and the code likes this:

{
    ......
    FD_ZERO(&fd_sets);
    FD_SET(sock_fd, &fd_sets);

    ret_val = select(sock_fd + 1, &fd_sets, NULL, NULL, NULL);

    if (ret_val > 0)
    {
         accept(sock_fd, NULL, NULL);
         ......
    }
    else
    {
        ......
    }

Per my understandings, if in other thread, shutdown the socket, and the code likes this:

{
    ......
    shutdown(sock_fd, SHUT_RD);
    ......
}

I think the select() in the previous thread should return. But after testing, I find the select() is still in blocking.

Why shutdown a socket can't let the select() return?

You might want to [read this](http://lists.gnu.org/archive/html/libmicrohttpd/2011-09/msg00026.html). It seems that Solaris doesn't unblock when you `shutdown` a listening socket. — Some programmer dude, Aug 21 '13 at 08:13
@JoachimPileborg: Yes, after check the return error code of shutdown, it is ENOTCONN (/* Socket is not connected */), so I think I should consider other methods to fix this issue. Thanks! — Nan Xiao, Aug 21 '13 at 08:29
You could consider a bit of error handling in your code, instead of just assuming everything works, and throwing away the result of accept(). If you'd done that you wouldn't be asking this question. — user207421, Aug 21 '13 at 09:49
@EJP: OK, thanks for your advice! This code is merely a demo, and I will add error handling in production code. — Nan Xiao, Aug 21 '13 at 10:00
No. Add it now. It's there for a purpose. Adding it in production is already too late, as this question proves. You're wasting your own time by deferring this. — user207421, Aug 21 '13 at 10:18

Why shutdown a socket can't let the select() return?

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