sc.cpp

linux socket编程客户端例子

#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>

#include   <netinet/in.h>
#include   <arpa/inet.h>


#define SERVPORT 3333 
#define MAXDATASIZE 100 /*每次最大数据传输量 */ 

main(int argc, char *argv[])
{ 
  int sockfd, 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); 
  } 
  
  if((host=gethostbyname(argv[1]))==NULL) 
  { 
    herror("gethostbyname出错！"); 
    exit(1); 
  } 
  
  if ((sockfd = 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(sockfd, (struct sockaddr *)&serv_addr,sizeof(struct sockaddr)) == -1) 
  { 
    perror("connect出错！"); 
    exit(1); 
  } 
  
  if ((recvbytes=recv(sockfd, buf, MAXDATASIZE, 0)) ==-1) 
  { 
    perror("recv出错！"); 
    exit(1); 
  } 
  
  buf[recvbytes] = '\0'; 
  printf("Received: %s",buf); 
  close(sockfd); 
}