（unix网络编程）时间获取程序

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <time.h>
#include <unistd.h>
#include <errno.h>

#define MAXLINE 4096
#define LISTENQ 5

int main(int argc, char **argv)
{
int listenfd, connfd;
struct sockaddr_in servaddr;
char buff[MAXLINE];
time_t ticks;

if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
printf("socket error\n");
return -1;
}

memset(&servaddr, 0x00, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
servaddr.sin_port = htons(5000);

if (bind(listenfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0) {
printf("bind error: %s\n", strerror(errno));
return -1;
}

if (listen(listenfd, LISTENQ) < 0) {
printf("listen error: %s\n", strerror(errno));
return -1;
}

for (;;) {
connfd = accept(listenfd, (struct sockaddr *)NULL, NULL);
ticks = time(NULL);
snprintf(buff, sizeof(buff), "%.24s\r\n", ctime(&ticks));
if ((write(connfd, buff, strlen(buff))) < 0)
printf("write error\n");

if(close(connfd) < 0)
printf("close error\n");
}
}

#include <stdio.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <errno.h>
#include <unistd.h>

#define MAXLINE 4096
int main(int argc, char **argv)
{
int sockfd, n;
char recvline[MAXLINE + 1];
struct sockaddr_in servaddr;

if (argc != 2) {
printf("usage: a.out <IPaddress>\n");
return -1;
}

if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
printf("socket error\n");
return -1;
}

memset(&servaddr, 0x00, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(5000);
if (inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0) {
printf("inet_pton error for %s\n", argv[1]);
return -1;
}

if (connect(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0) {
printf("connect error: %s\n", strerror(errno));
return -1;
}

while ((n = read(sockfd, recvline, MAXLINE)) > 0) {
recvline
= 0;
if (fputs(recvline, stdout) == EOF)
printf("fputs error\n");
}

if (n < 0)
printf("read error\n");

return 0;
}