C/C++TCP套接字服务器读取

我想创建一个服务器和客户端，在linux上运行，这样

1. 连接已建立
2. 客户端向服务器发送消息
3. 服务器向客户端发送响应
4. 端部连接

使用http://www.thegeekstuff.com/2011/12/c-socket-programming/，这就是我想到的。

TCPSockets.cpp

#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 <iostream>
int createConnection(char *ipaddr)
{
    int sockfd = 0;
    struct sockaddr_in serv_addr;
    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(5000);
    if(inet_pton(AF_INET, ipaddr, &serv_addr.sin_addr)<=0)
    {
        printf("n inet_pton error occuredn");
        return -1;
    }
    if( connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
    {
       printf("n Error : Connect Failed n");
       return -1;
    }
    return sockfd;
}
void receiveMessage(int sockfd)
{
    int n = 0;
    char recvBuff[1024];
    memset(recvBuff, '0',sizeof(recvBuff));
    while ( (n = read(sockfd, recvBuff, sizeof(recvBuff)-1)) > 0)
    {
        std::cout<<"recvBuff="<<recvBuff<<std::endl;
        recvBuff[n] = 0;
        if(fputs(recvBuff, stdout) == EOF)
        {
            printf("n Error : Fputs errorn");
        }
    }
    if(n < 0)
    {
        printf("n Read error n");
    }
}
int createListeningSocket()
{
    int listenfd = 0;
    struct sockaddr_in serv_addr;
    listenfd = socket(AF_INET, SOCK_STREAM, 0);
    memset(&serv_addr, '0', sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(5000);
    bind(listenfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr));
    listen(listenfd, 10);
    return listenfd;
}
void sendMessage(int connfd, char * format) {
    char sendBuff[1025];
    memset(sendBuff, '0', sizeof(sendBuff));
    snprintf(sendBuff, sizeof(sendBuff), format);
    write(connfd, sendBuff, strlen(sendBuff));
}

服务器.cpp

#include "TCPSockets.cpp"
int main(int argc, char *argv[]) {
    std::cout<<"Creating socket..."<<std::endl;
    int listeningSocketDescriptor = createListeningSocket();
    std::cout<<"Socket created."<<std::endl;
    std::cout<<"Waiting for connection..."<<std::endl;
    int clientSocketDescriptor = accept(listeningSocketDescriptor, (struct sockaddr*)NULL, NULL);
    std::cout<<"Connection made."<<std::endl;
    std::cout<<"Waiting for message..."<<std::endl;
    receiveMessage(listeningSocketDescriptor);
    std::cout<<"Message received."<<std::endl;
    std::cout<<"Sending message..."<<std::endl;
    sendMessage(clientSocketDescriptor, "From server!");
    std::cout<<"Message sent."<<std::endl;
    std::cout<<"Closing client socket..."<<std::endl;
    close(clientSocketDescriptor);
    std::cout<<"Client socket closed."<<std::endl;
    close(listeningSocketDescriptor);
    return 0;
}

客户端.cpp

#include "TCPSockets.cpp"
int main(int argc, char *argv[]) {
    if(argc != 2)
    {
        printf("n Usage: %s <ip of server> n",argv[0]);
        return 1;
    }
    std::cout<<"Creating connection..."<<std::endl;
    int socketDescriptor = createConnection(argv[1]);
    if (socketDescriptor < 0)
    {
        return 1;
    }
    std::cout<<"Connection created."<<std::endl;
    std::cout<<"Sending message..."<<std::endl;
    sendMessage(socketDescriptor, "From client!");
    std::cout<<"Message sent."<<std::endl;
    std::cout<<"Waiting for response..."<<std::endl;
    receiveMessage(socketDescriptor);
    std::cout<<"Response received."<<std::endl;
    return 0;
}

除了服务器接收消息外，其他一切都正常工作。我做错了什么？