socket网络编程小例子
服务器端程序：
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#define PORT 2370
#define BACKLOG 2
#define IP "127.0.0.1"
void process_conn_server(int s,char * ip);
int main(int argc,char *argv[])
{
int ss,sc;
struct sockaddr_in server_addr;
struct sockaddr_in client_addr;
int err;
pid_t pid;
//创建套接字
ss=socket(AF_INET,SOCK_STREAM,0);
if(ss<0)
{
printf("socket error\n");
return -1;
}
//设置服务器端的地址，端口等
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(PORT);
server_addr.sin_addr.s_addr = INADDR_ANY;
bzero(&(server_addr.sin_zero), 8);
//将创建的套接字绑定到服务器端
err = bind(ss, (struct sockaddr *)&server_addr, sizeof(struct sockaddr)); if(err<0)
{
printf("bind error\n");
return -1;
}
//监听套接字
err=listen(ss,BACKLOG);
if(err<0)
{
printf("listen error\n");
return -1;
}
//主循环程序
for(;;)
{
int addrlen=sizeof(struct sockaddr);
sc=accept(ss,(struct sockaddr*)&client_addr,&addrlen);//如果调用成功，https://www.wendangku.net/doc/4515231759.html,将返回一个新的套接字与客户端通信
printf("%s has connected success\n",inet_ntoa(client_addr.sin_addr)); if(sc<0)
{
continue;
}
pid=fork();//创建一个进程与客户端通信
if(pid==0)
{
close(ss);//为了避免影响，在子进程中关闭父进程套接字，父进程关闭子进
程的套接字（并没有真正的关闭，只是让它们不相互影响）
process_conn_server(sc,inet_ntoa(client_addr.sin_addr));//调用子进
程通信函数
}
else
{
close(sc);
}
}
}
void process_conn_server(int s,char *ip)
{
char buffer[1024];
while(1)
{
memset(buffer,'\0',1024); //置空
recv(s,buffer,1024,0);//接收消息https://www.wendangku.net/doc/4515231759.html,
if(strncmp("end",buffer,3)==0)//判断是否符合退出条件
{
printf("%s has lost connect\n",ip);
close(s);
exit(EXIT_SUCCESS);
}
printf("%s say :%s\n",ip,buffer);
//统计客户端输出的字符个数并发送给客户端
sprintf(buffer,"%d characters altogether",strlen(buffer)-1); send(s,buffer,1024,0);
}
}
客户端程序：
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#define IP "127.0.0.1"
#define PORT 2370
#define TEST
void process_conn_client(int s);
void signal_g();
int main(int argc,char *argv[])
{
int s;
struct sockaddr_in server_addr;
int err;
//创建套接字
s=socket(AF_INET,SOCK_STREAM,0);
if(s<0)
{
printf("socket erro\n");
return -1;
}
//设置服务器端的地址，端口等
server_addr.sin_family=AF_INET;
server_addr.sin_addr.s_addr=inet_addr(IP);//字符串类型转IP类型
server_addr.sin_port=htons(PORT);
bzero(&(server_addr.sin_zero),8);
#ifndef TEST
printf("a");
#endif
connect(s,(struct sockaddr *)&server_addr,sizeof(struct sockaddr));//连接服务器
#ifndef TEST
printf("b");
#endif
process_conn_client(s);
close(s);
}
void process_conn_client(int s)
{
ssize_t size=0;
char buffer[1024];
signal(SIGINT ,signal_g);//捕捉中断信号（Ctrl+C键），使必须输入“end”才能结束
while(1)
{
memset(buffer,'\0',1024);
fgets(buffer,1024,stdin);
send(s, buffer, 1024, 0);
if(strncmp("end",buffer,3)==0)
{
break;
}
memset(buffer,'\0',1024);
recv(s,buffer,1024,0);//接收服务器端发来的信息
printf("%s\n",buffer);
}
}
void signal_g()//信号处理函数
{
signal(SIGINT,SIG_IGN);
}
Linux下测试结果如下图（程序只支持由客户端向服务器发数据，其他功能读者自行添加）