/*******服务器程序 TCPServer.c ************/
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#define WAITBUF 1
int main()
{
int sockfd,new_fd;
struct sockaddr_in server_addr;
struct sockaddr_in client_addr;
int sin_size,portnumber;
char hello[]="Socket communication world!\n";
int i;
//if(argc!=2)
//{
//fprintf(stderr,"Usage:%s portnumber\a\n",argv[0]);
// exit(1);
//}
/*端口号不对，退出*/
//if((portnumber=atoi(argv[1]))<0)
//{
// fprintf(stderr,"Usage:%s portnumber\a\n",argv[0]);
//exit(1);
//}
/*服务器端开始建立socket描述符*/
if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1)
{
fprintf(stderr,"Socket error:%s\n\a",strerror(errno));
exit(1);
}
portnumber=23;
/*服务器端填充 sockaddr结构*/
bzero(&server_addr,sizeof(struct sockaddr_in));
server_addr.sin_family=AF_INET;
/*自动填充主机IP*/
server_addr.sin_addr.s_addr=INADDR_ANY;
server_addr.sin_port=htons(portnumber);
/*捆绑sockfd描述符*/
if(bind(sockfd,(struct sockaddr *)(&server_addr),sizeof(struct sockaddr))==-1)
{
fprintf(stderr,"Bind error:%s\n\a",strerror(errno));
exit(1);
}
/*监听sockfd描述符*/
if(listen(sockfd, WAITBUF)==-1)
{
fprintf(stderr,"Listen error:%s\n\a",strerror(errno));
exit(1);
}
while(1)
{
/*服务器阻塞，直到客户程序建立连接*/
sin_size=sizeof(struct sockaddr_in);
if((new_fd=accept(sockfd,(struct sockaddr *)(&client_addr),&sin_size))==-1)
{
fprintf(stderr,"Accept error:%s\n\a",strerror(errno));
exit(1);
}
/*可以在这里加上自己的处理函数*/
fprintf(stderr,"Server get connection from %s\n",inet_ntoa(client_addr.sin_addr));
if(send(new_fd,hello,strlen(hello),0)==-1)
{
fprintf(stderr,"Write Error:%s\n",strerror(errno));
exit(1);
}
close(new_fd);
}
/*这个通信已经结束*/
/*循环下一个*/
close(sockfd);
exit(0);
}
/******* 客户端程序 TCPClient.c ************/
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#define RECVBUFSIZE 1024
int main(int argc, char *argv[])
{
int sockfd;
char buffer[RECVBUFSIZE];
struct sockaddr_in server_addr;
struct hostent *host;
int portnumber,nbytes;
*if(argc!=3)
{
fprintf(stderr,"Usage:%s hostname portnumber\a\n",argv[0]);
exit(1);
}
if((portnumber=atoi(argv[2]))<0)
{
fprintf(stderr,"Usage:%s hostname portnumber\a\n",argv[0]);
exit(1);
}
/*客户程序开始建立 sockfd描述符*/
if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1)
{
fprintf(stderr,"Socket Error:%s\a\n",strerror(errno));
exit(1);
}
/*客户程序填充服务端的资料*/
bzero(&server_addr,sizeof(server_addr));
server_addr.sin_family=AF_INET;
server_addr.sin_port=htons(portnumber);
server_addr.sin_addr.s_addr = inet_addr(argv[1]);
/*客户程序发起连接请求*/
if(connect(sockfd,(struct sockaddr *)(&server_addr),sizeof(struct sockaddr))==-1)
{
fprintf(stderr,"Connect Error:%s\a\n",strerror(errno));
exit(1);
}
/*连接成功*/
if((nbytes=recv(sockfd,buffer, RECVBUFSIZE),0)==-1)
{
fprintf(stderr,"Read Error:%s\n",strerror(errno));
exit(1);
}
buffer[nbytes]='\0';
printf("I have received:%s\n",buffer);
/*结束通讯*/
close(sockfd);
exit(0);
}
