用C++写一个点对点的通信系统

好的，我可以为您提供一个基于C语言的点对点通信系统的代码示例：

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

#define PORT 8888

int main(int argc, char *argv[]) {
    int sockfd, ret;
    struct sockaddr_in serverAddr, clientAddr;
    char buffer[1024];

    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0) {
        printf("Error creating socket!\n");
        exit(1);
    }
    printf("Socket created...\n");

    memset(&serverAddr, 0, sizeof(serverAddr));
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_addr.s_addr = INADDR_ANY;
    serverAddr.sin_port = htons(PORT);

    ret = bind(sockfd, (struct sockaddr*)&serverAddr, sizeof(serverAddr));
    if (ret < 0) {
        printf("Error binding!\n");
        exit(1);
    }
    printf("Binding done...\n");

    printf("Listening for incoming connections...\n");
    listen(sockfd, 10);

    while (1) {
        socklen_t len = sizeof(clientAddr);
        int clientfd = accept(sockfd, (struct sockaddr*)&clientAddr, &len);
        if (clientfd < 0) {
            printf("Error accepting connection!\n");
            exit(1);
        }
        printf("Connection accepted...\n");

        memset(buffer, 0, sizeof(buffer));
        printf("Enter your message: ");
        fgets(buffer, sizeof(buffer), stdin);

        ret = send(clientfd, buffer, strlen(buffer), 0);
        if (ret < 0) {
            printf("Error sending message!\n");
            exit(1);
        }
        printf("Message sent to client...\n");

        close(clientfd);
    }

    return 0;
}

这个代码示例实现了一个简单的点对点通信系统，使用了TCP协议进行通信。您可以根据需要进行修改和扩展。