client.c.txt

这是一款很通用的linux下的TCP通讯编程。适合于嵌入式linux平台网络编程的开发等相关研究。

#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<errno.h>
#include<string.h>
#include<netdb.h>
#include<sys/types.h>
#include<netinet/in.h>
#include<sys/socket.h>
#define PORT 3490 //the port client will be connecting to 
#define MAXDATASIZE 100//max number of bytes we can get at once 
int main(int argc,char *argv[]){
   int sockfd,numbytes;
   char buf[MAXDATASIZE];
   struct hostent *he;
   struct sockaddr_in their_addr;//connector's address information

   if(argc!=2){
     fprintf(stderr,"usage:client hostname\n");
     exit(1);
     }
   if((he=gethostbyname(argv[1]))==NULL){//get the host information
     perror("gethostbyname");
     exit(1);
     }
   if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1){
      perror("socket");
      exit(1);
      }
   their_addr.sin_family=AF_INET;//host byte order
   their_addr.sin_port=htons(PORT);//short,network byte order
   their_addr.sin_addr=*((struct in_addr *)he->h_addr);
   memset(&(their_addr.sin_zero),'\0',8);//zero the rest struct
   if(connect(sockfd,(struct sockaddr*)&their_addr,sizeof(struct          sockaddr))==-1){
      perror("connect");
      exit(1);
      }
   if((numbytes=recv(sockfd,buf,MAXDATASIZE-1,0))==-1){
      perror("recv");
      exit(1);
      }
   buf[numbytes]='\0';
   printf("Received:%s",buf);
   close(sockfd);
   return 0;
 }
 }