bcast_test.c

void
dg_cli(FILE *fp, int sockfd, const SA *pservaddr, socklen_t servlen)
{
    int        n;
    const int    on = 1;
    char      sendline[MAXLINE], recvline[MAXLINE + 1];
    socklen_t    len;
    struct sockaddr  *preply_addr;

    preply_addr = Malloc(servlen);

    Setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on));

    Signal(SIGALRM, recvfrom_alarm);

    while (Fgets(sendline, MAXLINE, fp) != NULL) {

        Sendto(sockfd, sendline, strlen(sendline), 0, pservaddr, servlen);
#if 0
        alarm(5);
        for ( ; ; ) {
            len = servlen;
            n = recvfrom(sockfd, recvline, MAXLINE, 0, preply_addr, &len);
            if (n < 0) {
                if (errno == EINTR)
                    break;    /* waited long enough for replies */
                else
                    err_sys("recvfrom error");
            } else {
                recvline[n] = 0;  /* null terminate */
                printf("from %s: %s",
                        Sock_ntop_host(preply_addr, servlen), recvline);
            }
        }
#endif
    }
}

static void
recvfrom_alarm(int signo)
{
    return;    /* just interrupt the recvfrom() */
}