couldn't check remote was closed

[sydnash]

local data, status, partial = self.tcp:receive("_a")
if __status == STATUS_CLOSED or _status == STATUS_NOT_CONNECTED then
--remote was closed.
end
I use code above to check remote socket is closed，but the status is allways timeout because the code at wsocket.c（socket_waitfd）：
if (timeout_iszero(tm)) return IO_TIMEOUT; / optimize timeout == 0 case */
because my socket is non-blocking，so it allways return timeout here。after delete this line，it's return closed。

[diegonehab]

Maybe this could happen on the first call. But on the second call, it should return IO_CLOSED, no?

[sydnash]

yes,not fist call,it allways return timeout,
until i comment this line（if (timeout_iszero(tm)) return IO_TIMEOUT; / optimize timeout == 0 case */）.

[epajarre]

Just saying "Me too". Also experiencing this problem with my program, and while searching found this thread. Looks like sydnash is correct.

[darklost]

/* On UDP, a connreset simply means the previous send failed.
* So we try again.
* On TCP, it means our socket is now useless, so the error passes.
* (We will loop again, exiting because the same error will happen) */

as this in wsocket.c line 256 try again but may it missing continue ? prev still IO_DONE
in if (err != WSAECONNRESET || prev == WSAECONNRESET) return err;

int socket_recv(p_socket ps, char *data, size_t count, size_t *got, 
        p_timeout tm) 
{
    int err, prev = IO_DONE;
    *got = 0;
    if (*ps == SOCKET_INVALID) return IO_CLOSED;
    for ( ;; ) {
        int taken = recv(*ps, data, (int) count, 0);
        if (taken > 0) {
            *got = taken;
            return IO_DONE;
        }
        if (taken == 0) return IO_CLOSED;
        err = WSAGetLastError();
        /* On UDP, a connreset simply means the previous send failed. 
         * So we try again. 
         * On TCP, it means our socket is now useless, so the error passes. 
         * (We will loop again, exiting because the same error will happen) */
        if (err != WSAEWOULDBLOCK) {
                        if (err != WSAECONNRESET || prev == WSAECONNRESET) return err;
                        prev = err;
			//change by  2017-1-7 01:59:38 darklost.me
			//settimeout(0) is always return IO_TIMEOUT when remote server is closed!
			//maybe missing continue here?
			continue;
        }
        if ((err = socket_waitfd(ps, WAITFD_R, tm)) != IO_DONE) return err;
    }
}

in function int socket_recvfrom(p_socket ps, char *data, size_t count, size_t *got, SA *addr, socklen_t *len, p_timeout tm) the same as above

may be missing continue ?

[alerque]

Does #81 help with figuring out if the remote side closed?

[jakitliang]

I wonder this change would dead loop doing socket the block check.
On Windows, read() is block even though using MSG_*** parameters. Except to setting the non-block flag.
I think the best way is to Select again instead loop it with continue.