Linux 网络编程：多客户请求服务器（ C/S ）实例

注意：可以开启一个server和多个client，同时可以对server进行发送data处理,请注意client的参数，格式是：./client  IP   char_data
IP：就是server所在的IP，char_data就是发送的数据
 
server.c

#include<sys/types.h>
#include<sys/socket.h>
#include<strings.h>
#include<arpa/inet.h>
#include<unistd.h>
#include<stdlib.h>
#include<stdio.h>
#include<string.h>
#include<errno.h>
#include<signal.h>
#include<sys/wait.h>

#define  

  LISTEN_PORT  6000        //!> 端口
#define    MAX               5            //!> 最大的等待请求数目

void str_echo( int sockfd)                //!> 从client中读取数据
{
   ssize_t       n;
    charline[512];
   
   printf("准备读数据：");
   
    while( 1)
    {
       while( ( n =read( sockfd, line, 512 ) ) > 0)      //!> 注意是：根据accept得到的client的操作描述符来处理的呗～
       {
          line[n] ='\0';
         printf("Client  send: %s\n", line );
          bzero(&line, sizeof( line ));      //!> 再次置NULL
       }
    }
}

int main( int argc, char ** argv )
{
    int             listenfd,connfd;      //!> 描述符
   pid_t         childpid;            //!> 子进程号
   socklen_t      chilen;               //!>
   
    structsockaddr_in chiaddr, servaddr;
   
   //!> 建立socket( TCP )
   //!>
    if( (listenfd = socket( AF_INET, SOCK_STREAM, 0 ) ) == -1 )
    {
      printf("socket error... :  %s\n",(char*)strerror(errno));
       exit(EXIT_FAILURE );
    }
   
   //!> socket参数
   //!>
   servaddr.sin_family =AF_INET;                  //!> 协议族
   servaddr.sin_port = htons( LISTEN_PORT);      //!> IP
   servaddr.sin_addr.s_addr =INADDR_ANY;      //!> 本机IP
    bzero(&( servaddr.sin_zero ), 8);               //!> 8字节填充字符

   //!> 绑定IP和端口
   //!>
    if( bind(listenfd, ( struct sockaddr * )&servaddr, sizeof(servaddr ) ) == -1 )
    {
      printf("bind失败\n");
       exit(EXIT_FAILURE );
    }

   //!> 下面开始监听
   //!>   
    if( listen(listenfd, MAX ) == -1 )
    {
      printf("listen error...");
       exit(EXIT_FAILURE );
    }
   
    while( 1)
    {
       chilen =sizeof( chiaddr );
      
      //!> 等待连接
      //!>
       if( ( connfd= accept( listenfd, ( struct sockaddr* )&chiaddr,&chilen ) ) == -1 )
       {
         printf("accept error...\n");
          exit(EXIT_FAILURE );
       }
       else
       {
         printf("client连接成功！\n");
      }      
      
      //!> 创建子进程来处理请求
      //!>
       if( (childpid = fork() ) == 0 )
       {
          close(listenfd );            //!> server关闭与其链接，交给子进程处理
         printf("Client from %s\n", inet_ntoa( chiaddr.sin_addr ));
          str_echo(connfd );
          exit(EXIT_SUCCESS );
       }
       else if(childpid < 0 )
       {
          printf("forkerror...\n");
          close(connfd );
          exit(EXIT_FAILURE );
       }
      
       close(connfd );
    }
   
    return0;
}


client.c

#include<sys/types.h>
#include<stdlib.h>
#include<stdio.h>
#include<unistd.h>
#include<sys/socket.h>
#include<strings.h>
#include<string.h>
#include<arpa/inet.h>
#include<errno.h>

#define    SERVER_PORT   6000

void str_cli( char * data, int sockfd)            //!> 此处是client发送消息而已
{   
    while( 1)
    {
       write(sockfd, data, strlen( data ) );
       sleep( 1);
    }
   
    exit( 0);
}

int main( int argc, char ** argv )
{
    intsockfd;
    structsockaddr_in servaddr;
   
    if( argc !=3 )
    {
      printf("输入参数！\n");
       exit(EXIT_FAILURE );
    }
   
    if( ( sockfd= socket( AF_INET, SOCK_STREAM, 0 ) ) == -1 )
    {
      printf("socket error...\n");
       exit(EXIT_FAILURE );
    }
   
    bzero(&servaddr, sizeof( servaddr ) );
   servaddr.sin_family = AF_INET;
   servaddr.sin_port = htons( SERVER_PORT );
    inet_pton(AF_INET, argv[1], &servaddr.sin_addr);      //!> 需要自己写入IP 作为第一个参数

   printf("Client connecting...\n");
   
    if( connect(sockfd, ( struct sockaddr * )&servaddr, sizeof(servaddr ) ) == -1 )
    {
      printf("connect error..\n");
       exit(EXIT_FAILURE );
    }
   
   printf("开始发送data：\n");
    str_cli(argv[2], sockfd );

    return0;
}


makefile:

all: server client

server:
    gcc -W-o  server server.c
   
   
client:   
   gcc  -W -o client client.c
   
   
clean:
    rm -f serverclient