Question

所以我很困惑如何让服务器多次与我的客户端来回发送数据。目前，服务器将数据发送到客户端，然后客户端将发回答案，但我不知道如何多次这样做，而无需一次又一次地启动客户端服务器。

基本上我想知道如何在不创建新客户端的情况下让服务器和客户端重复通信。

这是我的服务器代码。我正在创建一个随机数，然后使用客户端确定其因素

#include <iostream>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <time.h> 
#include <cmath>

using namespace std;

int *findPrimes(int primeArray[])
{
    int i, j, n = 100000, flag;
    //int primeArray[65];
    int count = 0;

    for(i = 2; i <= n; i++)
    {
        flag = 1;
        for(j =2;j<=i/2;j++)
        {
            if(i%j==0)
            {
                flag = 0;
                break;
            }
        }
        if(flag==1)
        {
            primeArray[count] = i;
            count++;
        }
    }
    return primeArray;
}

int calcNumber()
{
    srand(time(NULL));

    int base = rand()%9 + 2;
    int numCalc[5];
    bool isntBase = false;
    int count = 0;
    int testNum;

    do{
        testNum = rand() % 100000;
        int number = testNum;
        cout << base << ", " << number << endl;
        count = 0;
        isntBase = false;

        for(int i = 0; i < 5; i++)
        {
            numCalc[i] = 0;
        }

        while (number > 0)
        {
            int digit = number%10;
            number /= 10;
            numCalc[count] = digit;
            count++;
            if(digit >= base)
            {
                isntBase = true;
            }
        }
    }while(isntBase == true);

    cout << testNum << "(" << base <<")";
    int decConvert = 0;
    int baseMult = 1;
    for(int i = 0; i < 5; i++)
    {
        //cout << numCalc[i] << endl;
        decConvert += numCalc[i]*(pow(base, i));
        //baseMult = baseMult * 7;
        //cout << decConvert << endl;
    }
    cout << " = " << decConvert << "(10) = ";
    return decConvert;
}


int main(int argc, char *argv[])
{
    int listenfd = 0, connfd = 0;
    struct sockaddr_in serv_addr; 

    char sendBuff[1025];
    time_t ticks; 

    int n = 3;
    int numOfPrime= 0;
    bool isPrime = false;
    bool noMorePlease = false;
    int y[9592];
    int *prime = findPrimes(y);

    int number = calcNumber();

    listenfd = socket(AF_INET, SOCK_STREAM, 0);
    memset(&serv_addr, '0', sizeof(serv_addr));
    memset(sendBuff, '0', sizeof(sendBuff)); 

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(5575); 

    bind(listenfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)); 

    listen(listenfd, 2); 

    int prcount = 0;

    while(noMorePlease == false){
        //Thread

        int client_socket;
        client_socket = accept(listenfd, NULL, NULL);

        int primeNum = prime[prcount];
        send(client_socket, &number, sizeof(number),0);
        send(client_socket, &primeNum,sizeof(primeNum), 0);

        int recvNum = 0;
        //char recvVal[256];   
        //recv(listenfd, &number, sizeof(number), 0);
        recv(client_socket, &recvNum, sizeof(recvNum), 0);

        //cout << endl << recvNum;

        if(recvNum >0)
        {
            cout << prime[prcount] << "^" << recvNum <<"*";
        }
        while(recvNum > 0)
        {
            number = number/prime[prcount];
            recvNum--;
        }
        prcount++;
        if(number == 1)
        {
            cout << endl;
            numOfPrime = 0;
            noMorePlease = true;
        }
        if(prcount > 9592)
        {
            numOfPrime++;
            cout << " a prime number!" << endl;
            numOfPrime++;
            if(numOfPrime == n)
            {
                noMorePlease = true;
                cout << "There were " << n << " primes in a row" << endl;
                close(listenfd);
                return 0;
            }
        }
        //close(client_socket);
    }

    close(listenfd);
    return 0;
}

这是我的客户代码

#include <iostream>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <arpa/inet.h> 

using namespace std;

int main(int argc, char *argv[])
{
    int sockfd = 0, n = 0;
    char recvBuff[1024];
    struct sockaddr_in serv_addr; 


    if(argc != 2)
    {
        printf("\n Usage: %s <ip of server> \n",argv[0]);
        return 1;
    } 

    memset(recvBuff, '0',sizeof(recvBuff));
    if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
    {
        printf("\n Error : Could not create socket \n");
        return 1;
    } 

    memset(&serv_addr, '0', sizeof(serv_addr)); 

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(5575); 

    if(inet_pton(AF_INET, argv[1], &serv_addr.sin_addr)<=0)
    {
        printf("\n inet_pton error occured\n");
        return 1;
    } 

    if( connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
    {
       printf("\n Error : Connect Failed \n");
       return 1;
    } 
    int number = 0;
    int primeNum;
    char recvVal[256];   
    recv(sockfd, &number, sizeof(number), 0);
    recv(sockfd, &primeNum, sizeof(primeNum), 0);

    int divCount = 0;

    cout << number << ", " << primeNum << endl;
    while(number % primeNum == 0)
    {
        cout << number << ",  ";
        number =  number/primeNum;
        divCount++;
    }

    cout << endl << divCount;
    send(sockfd, &divCount,sizeof(divCount), 0);

    /*
    while ( (n = read(sockfd, recvBuff, sizeof(recvBuff)-1)) > 0)
    {
        recvBuff[n] = 0;
        if(fputs(recvBuff, stdout) == EOF)
        {
            printf("\n Error : Fputs error\n");
        }
    } 

    if(n < 0)
    {
        printf("\n Read error \n");
    } 
*/
    close(sockfd);
    return 0;
}

Answer 1

在您的客户端代码中，在行之后：

operator>>

您应该在循环中执行 recv 和发送，以便连接保持打开状态。完成后，退出循环并关闭套接字。可以在此处找到使用同步套接字的此方法的示例：https://vcansimplify.wordpress.com/2013/03/14/c-socket-tutorial-echo-server/

c ++ linux socket服务器反复调用客户端

1 个答案: