Only read readable sockets.

src/syncterm/rlogin.c

@@ -29,7 +29,6 @@ rlogin_input_thread(void *args)
 			rd = recv(rlogin_sock, conn_api.rd_buf, conn_api.rd_buf_size, 0);
 			if (rd <= 0)
 				break;
-		}
 			buffered = 0;
 			while (rlogin_sock != INVALID_SOCKET && buffered < rd) {
 				pthread_mutex_lock(&(conn_inbuf.mutex));
@@ -38,6 +37,7 @@ rlogin_input_thread(void *args)
 				pthread_mutex_unlock(&(conn_inbuf.mutex));
 			}
 		}
+	}
 	conn_api.input_thread_running = 2;
 }