SO_KEEPALIVE 72 ext/mysqlnd/mysqlnd_net.c int result = setsockopt(socketd, SOL_SOCKET, SO_KEEPALIVE, (char *) &flag, sizeof(int)); SO_KEEPALIVE 674 ext/sockets/sockets.c REGISTER_LONG_CONSTANT("SO_KEEPALIVE", SO_KEEPALIVE, CONST_CS | CONST_PERSISTENT);