receive_message
receive_message(daemon_fd, (char *)&shmid, sizeof(shmid));
receive_message(daemon_fd, (char *)&error, sizeof(error));
receive_message(daemon_fd, (char *)&ret, sizeof(ret));
receive_message(daemon_fd, (char *)buf, sizeof(*buf));
receive_message(daemon_fd, (char *)&error, sizeof(error));
int receive_message(int, char *, int);