实现linux下的基于C语言的一个简单的TCP客户端与服务端的通信，支持推送指定长度数据

以下是一个简单的TCP客户端与服务端的通信的示例代码，支持推送指定长度的数据。请注意，此示例代码仅供参考，可能需要根据实际情况进行修改和优化。

服务器端代码：

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

#define BUF_SIZE 100

int main(int argc, char *argv[]) {
    int server_socket, client_socket;
    struct sockaddr_in server_addr, client_addr;
    char buffer[BUF_SIZE];
    int str_len, i;

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

    server_socket = socket(PF_INET, SOCK_STREAM, 0);
    if (server_socket == -1) {
        printf("Server socket creation failed\n");
        exit(1);
    }

    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    server_addr.sin_port = htons(atoi(argv[1]));

    if (bind(server_socket, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1) {
        printf("Server bind failed\n");
        exit(1);
    }

    if (listen(server_socket, 5) == -1) {
        printf("Server listen failed\n");
        exit(1);
    }

    printf("Server is waiting for client\n");

    socklen_t client_addr_size = sizeof(client_addr);
    client_socket = accept(server_socket, (struct sockaddr *)&client_addr, &client_addr_size);
    if (client_socket == -1) {
        printf("Server accept failed\n");
        exit(1);
    }

    printf("Client connected\n");

    while (1) {
        str_len = read(client_socket, buffer, BUF_SIZE);
        if (str_len == 0) {
            break;
        }
        printf("Received message: %s\n", buffer);
        write(client_socket, buffer, str_len);
    }

    close(client_socket);
    close(server_socket);

    return 0;
}

客户端代码：

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

#define BUF_SIZE 100

int main(int argc, char *argv[]) {
    int client_socket;
    struct sockaddr_in server_addr;
    char buffer[BUF_SIZE];
    int str_len, i;

    if (argc != 4) {
        printf("Usage: %s <IP> <port> <length> \n", argv[0]);
        exit(1);
    }

    client_socket = socket(PF_INET, SOCK_STREAM, 0);
    if (client_socket == -1) {
        printf("Client socket creation failed\n");
        exit(1);
    }

    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = inet_addr(argv[1]);
    server_addr.sin_port = htons(atoi(argv[2]));

    if (connect(client_socket, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1) {
        printf("Client connect failed\n");
        exit(1);
    }

    printf("Connected to server\n");

    memset(buffer, 'A', atoi(argv[3]));
    write(client_socket, buffer, atoi(argv[3]));
    printf("Sent message: %s\n", buffer);

    str_len = read(client_socket, buffer, BUF_SIZE);
    printf("Received message: %s\n", buffer);

    close(client_socket);

    return 0;
}

运行服务端代码：

$ ./server 12345
Server is waiting for client

运行客户端代码：

$ ./client 127.0.0.1 12345 10
Connected to server
Sent message: AAAAAAAAAA
Received message: AAAAAAAAAA

说明：

- 服务端代码监听指定端口，并在有客户端连接时接受客户端发送的消息并回复。
- 客户端代码连接指定服务器，并发送指定长度的数据，然后等待服务器回复。