if (ioctlsocket (s, SIOCATMARK, &clear_of_oob) < 0 ) return -20000-WSAGetLastError();
ioctlsocket (s, SIOCATMARK, &clear_of_oob);
static int telnet_msg (WPARAM wParam, LPARAM lParam) {    int ret;    /* This needs to be larger than the packet size now that inbuf     * cannot overflow, in fact the fewer calls we make to windows     * the faster we will run!     */    char buf[16384];	    /*     * Because reading less than the whole of the available pending     * data can generate an FD_READ event, we need to allow for the     * possibility that FD_READ may arrive with FD_CLOSE already in     * the queue; so it's possible that we can get here even with s     * invalid. If so, we return 1 and don't worry about it.     */    if (s == INVALID_SOCKET)	return 1;    if (WSAGETSELECTERROR(lParam) != 0) {        closesocket(s);        s = INVALID_SOCKET;	return -WSAGETSELECTERROR(lParam);    }    switch (WSAGETSELECTEVENT(lParam)) {      case FD_READ:      case FD_CLOSE:	{	    int clear_of_oob = 1;	    if (ioctlsocket (s, SIOCATMARK, &clear_of_oob) < 0 )		return -20000-WSAGetLastError();	    in_synch = !clear_of_oob;	    do {		ret = recv(s, buf, sizeof(buf), 0);		if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)		    return 1;		if (ret < 0) {		       /* any _other_ error */                    closesocket(s);                    s = INVALID_SOCKET;		    return -10000-WSAGetLastError();                }		if (ret == 0) {		    s = INVALID_SOCKET;		    return 0;		}	        do_telnet_read (buf, ret);	    } while (in_synch);	}	return 1;      case FD_WRITE:	if (outbuf_head != outbuf_reap)	    try_write();	return 1;    }    return 1;			       /* shouldn't happen, but WTF */}