PHP_SAFE_FD_SET 198 main/php_network.h # define PHP_SAFE_FD_SET(fd, set) FD_SET(fd, set) PHP_SAFE_FD_SET 203 main/php_network.h # define PHP_SAFE_FD_SET(fd, set) do { if (fd < FD_SETSIZE) FD_SET(fd, set); } while(0)