daytimeudpcli1.c

来自「Unix网络编程 基于Socket的网络编程」· C语言 代码 · 共 34 行

#include	"unpxti.h"

int
main(int argc, char **argv)
{
	int					tfd, flags;
	char				recvline[MAXLINE + 1];
	socklen_t			addrlen;
	struct t_unitdata	*sndptr, *rcvptr;

	if (argc != 3)
		err_quit("usage: daytimeudpcli <hostname> <service>");

	tfd = Udp_client(argv[1], argv[2], (void **) &sndptr, &addrlen);

	rcvptr = T_alloc(tfd, T_UNITDATA, T_ADDR);

	printf("sending to %s\n", Xti_ntop_host(&sndptr->addr));

	sndptr->udata.maxlen = MAXLINE;
	sndptr->udata.len = 1;
	sndptr->udata.buf = recvline;
	recvline[0] = 0;		/* 1-byte datagram containing null byte */
	T_sndudata(tfd, sndptr);

	rcvptr->udata.maxlen = MAXLINE;
	rcvptr->udata.buf = recvline;
	T_rcvudata(tfd, rcvptr, &flags);
	recvline[rcvptr->udata.len] = 0;	/* null terminate */
	printf("from %s: %s", Xti_ntop_host(&rcvptr->addr), recvline);

	exit(0);
}