文章:
http://blog.youkuaiyun.com/hguisu/article/details/7445768/
程序:
客户端:
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <unistd.h>
#define SERVPORT 3333
#define MAXDATASIZE 100 /*每次最大数据传输量 */
int main(int argc, char *argv[])
{
int sock_fd, recvbytes;
char buf[MAXDATASIZE];
struct hostent *host;
struct sockaddr_in serv_addr;
if(argc< 2) {
fprintf(stderr,"Please enter the server's hostname!\n");
exit(1);
}
printf("%s", argv[1]);
if((host=gethostbyname("Mac-mini3.local")) == NULL) {
herror("gethostbyname出错!");
exit(1);
}
if((sock_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket创建出错!");
exit(1);
}
serv_addr.sin_family=AF_INET;
serv_addr.sin_port=htons(SERVPORT);
serv_addr.sin_addr = *((struct in_addr *)host->h_addr);
bzero(&(serv_addr.sin_zero),8);
if(connect(sock_fd, (struct sockaddr *)&serv_addr, sizeof(struct sockaddr)) == -1) {
perror("connect出错!");
exit(1);
}
//send
int retlen = ::send(sock_fd, "ok", 3, 0);
if (retlen < 0)
{
printf("\n send error");
}
//recv
if((recvbytes=recv(sock_fd, buf, MAXDATASIZE, 0)) == -1) {
perror("recv出错!");
exit(1);
}
buf[recvbytes] = '\0';
printf("Received: %s",buf);
close(sock_fd);
}
服务端:#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <unistd.h>
#include <arpa/inet.h>
#define SERVPORT 3333 /*服务器监听端口号 */
#define BACKLOG 10 /* 最大同时连接请求数 */
int main()
{
int sock_fd,client_fd; /*sock_fd:监听socket;client_fd:数据传输socket */
socklen_t sin_size;
struct sockaddr_in my_addr; /* 本机地址信息 */
struct sockaddr_in remote_addr; /* 客户端地址信息 */
if((sock_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket创建出错!");
exit(1);
}
my_addr.sin_family=AF_INET;
my_addr.sin_port=htons(SERVPORT);
my_addr.sin_addr.s_addr = INADDR_ANY;
bzero(my_addr.sin_zero,8);
if(bind(sock_fd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) {
perror("bind出错!");
exit(1);
}
if(listen(sock_fd, BACKLOG) == -1) {
perror("listen出错!");
exit(1);
}
while(1) {
sin_size = sizeof(struct sockaddr_in);
if((client_fd = accept(sock_fd, (struct sockaddr *)&remote_addr, &sin_size)) == -1) {
perror("accept出错");
continue;
}
//recv
char buff[3];
if(recv(client_fd, buff, 3, 0) == -1)
{
printf("recv error");
}
printf("%s\n", buff);
//send
printf("received a connection from %s\n", inet_ntoa(remote_addr.sin_addr));
if(!fork()) { /* 子进程代码段 */
if(send(client_fd, "Hello, you are connected!\n", 26, 0) == -1) {
perror("send出错!");
}
close(client_fd);
exit(0);
}
close(client_fd);
}
}