www.pudn.com > 11_code.rar > client.c

/*client.c*/ 
#include  
#include  
#include  
#include  
#include  
#include  
#include  
#include  
#define SERVPORT 3333 
#define MAXDATASIZE 100 
main(int argc,char *argv[]){ 
	int sockfd,sendbytes; 
	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); 
	} 
/*地址解析函数*/ 
	if((host=gethostbyname(argv[1]))==NULL){ 
		perror("gethostbyname"); 
		exit(1); 
	} 
/*创建socket*/ 
	if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1){ 
		perror("socket"); 
		exit(1); 
	} 
/*设置sockaddr_in 结构体中相关参数*/ 
	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); 
/*调用connect函数主动发起对服务器端的连接*/ 
	if(connect(sockfd,(struct sockaddr *)&serv_addr,\ 
		sizeof(struct sockaddr))==-1){ 
		perror("connect"); 
		exit(1); 
	} 
/*发送消息给服务器端*/ 
	if((sendbytes=send(sockfd,"hello",5,0))==-1){ 
		perror("send"); 
		exit(1); 
	} 
close(sockfd); 
}