//ser.cpp

#include <iostream>

#include <fcntl.h>

#include <sys/socket.h>

#include <sys/select.h>

#include <unistd.h>

#include <arpa/inet.h>

#include <netinet/in.h>

#include <string.h>

#define IP "127.0.0.1"

#define PORT 8888

using namespace std;

int main()

{

    int sockSer,sockCli;

    sockaddr_in addrSer,addrCli;

    sockSer = socket(AF_INET,SOCK_STREAM,0);

    bzero(&addrSer,sizeof(addrSer));

    bzero(&addrCli,sizeof(addrSer));

    addrSer.sin_family = AF_INET;

    addrSer.sin_port = htons(PORT);

    addrSer.sin_addr.s_addr = inet_addr(IP);

    socklen_t len = sizeof(sockaddr_in);

    bind(sockSer,(sockaddr*)&addrSer,len);

    listen(sockSer,5);

    char clibuff[255];

    memset(clibuff,0,sizeof(clibuff));

//////////////////////////////////////////////////////

fd_set Read;

fd_set Write;

static int maxfd = 0;

int sock_set[100];//socket set.

int size = 1;//index

sockCli = accept(sockSer,(sockaddr*)&addrCli,&len);

if(sockCli<0)

{

    cout<<sockCli<<endl;

    cout<<"accept() error!!!!"<<endl;

    close(sockSer);

    close(sockCli);

    return -1;

}

struct timeval _timeout={3,0};

off_t fd = open("a",O_CREAT|O_RDWR);

while(1)

{

 FD_ZERO(&Read);

 FD_SET(sockCli,&Read);

 FD_ZERO(&Write);

 FD_SET(fd,&Write);

 maxfd = maxfd>sockCli?

maxfd:sockCli;

 maxfd = maxfd>fd?maxfd:fd;

 select(maxfd+1,&Read,&Write,NULL,&_timeout);

 if(FD_ISSET(sockCli,&Read))

    {

        if(fork()==0)

        {

       cout<<"return"<<endl;

         char buff[255];

         memset(buff,0,sizeof(buff));

         while(1){

         read(sockCli,buff,sizeof(buff));

         cout<<buff<<endl;

         char str[]="xiaoyanzi";

         write(sockCli,str,strlen(str)+1);

         }

        }

     }

    if(FD_ISSET(fd,&Write))

        {

            write(fd,"1234",5);

            sleep(1);

        }

}

return 0;

}

#include <iostream>

#include <string.h>

#include <sys/socket.h>

#include <arpa/inet.h>

#include <netinet/in.h>

#define IP "127.0.0.1"

#define PORT 8888

using namespace std;

int main()

{

    int sockCli = socket(AF_INET,SOCK_STREAM,0);

    sockaddr_in addrSer;

    bzero(&(addrSer),sizeof(addrSer));

    addrSer.sin_family = AF_INET;

    addrSer.sin_port = htons(PORT);

    addrSer.sin_addr.s_addr = inet_addr(IP);

    socklen_t len = sizeof(sockaddr_in);

    int Ret = connect(sockCli,(sockaddr*)&addrSer,len);

    if(Ret != 0)

    {

        close(sockCli);

        return -1;

    }

    char serbuff[]="liuhuiyan";

    char clibuff[255];

    while(1)

    {

        write(sockCli,serbuff,strlen(serbuff)+1);

        read(sockCli,clibuff,sizeof(clibuff));

    cout<<clibuff<<endl;

        sleep(1);

    }

    return 0;

}

//Makefile

SER=ser

CLI=cli

CC=g++

Status=-g

all:$(CLI) $(SER)

.PHONY:all

$(SER):$(SER).cpp

    @$(CC) -o $@ $^ $(Status)

$(CLI):$(CLI).cpp

    @$(CC) -o $@ $^ $(Status)

.PHONY:clean

clean:

    rm -rf *.o $(SER) $(CLI)