FIONBIO           595 src/dps8/dps8_socket_dev.c # ifdef FIONBIO
FIONBIO           596 src/dps8/dps8_socket_dev.c     rc = ioctl (socket_fd, FIONBIO, (char *) & on);
FIONBIO           715 src/simh/sim_sock.c return ioctlsocket (sock, FIONBIO, &non_block);         /* set nonblocking */