#include "unp.h" static void recvfrom_alarm(int); 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); alarm(1); for ( ; ; ) { len = servlen; n = recvfrom(sockfd, recvline, MAXLINE, 0, preply_addr, &len); if (n == -1) { if (errno == EINTR) break; /* waited long enough for replies */ else err_sys("recvfrom error"); } else { recvline[n] = 0; /* null terminate */ sleep(1); printf("from %s: %s", Sock_ntop_host(preply_addr, len), recvline); } } } free(preply_addr); } static void recvfrom_alarm(int signo) { return; /* just interrupt the recvfrom() */ }