要實現消息推送功能，可以使用C語言的網絡編程相關庫進行開發。以下是一個簡單的示例代碼，使用了Linux下的socket編程：

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

#define SERVER_PORT 8888
#define MAX_CONNECTIONS 10
#define MAX_BUFFER_SIZE 1024

// 處理客戶端連接請求
void handleClient(int clientSocket) {
    char buffer[MAX_BUFFER_SIZE];
    memset(buffer, 0, sizeof(buffer));

    // 接收客戶端消息
    int bytesRead = recv(clientSocket, buffer, sizeof(buffer), 0);
    if (bytesRead <= 0) {
        printf("Failed to receive message from client.\n");
        close(clientSocket);
        return;
    }

    // 打印客戶端消息
    printf("Received message from client: %s\n", buffer);

    // 處理消息，這里可以根據需求進行具體的處理邏輯

    // 發送響應給客戶端
    char response[] = "Message received!";
    if (send(clientSocket, response, sizeof(response), 0) <= 0) {
        printf("Failed to send response to client.\n");
    }

    close(clientSocket);
}

int main() {
    int serverSocket, clientSocket;
    struct sockaddr_in serverAddr, clientAddr;
    socklen_t clientAddrLen = sizeof(clientAddr);

    // 創建套接字
    serverSocket = socket(AF_INET, SOCK_STREAM, 0);
    if (serverSocket == -1) {
        printf("Failed to create socket.\n");
        return -1;
    }

    // 設置地址重用
    int reuse = 1;
    if (setsockopt(serverSocket, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) == -1) {
        printf("Failed to set socket options.\n");
        return -1;
    }

    // 綁定地址和端口
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(SERVER_PORT);
    serverAddr.sin_addr.s_addr = INADDR_ANY;
    if (bind(serverSocket, (struct sockaddr *)&serverAddr, sizeof(serverAddr)) == -1) {
        printf("Failed to bind socket.\n");
        return -1;
    }

    // 開始監聽連接
    if (listen(serverSocket, MAX_CONNECTIONS) == -1) {
        printf("Failed to listen on socket.\n");
        return -1;
    }

    printf("Server started, listening on port %d.\n", SERVER_PORT);

    // 接受客戶端連接請求并處理
    while (1) {
        clientSocket = accept(serverSocket, (struct sockaddr *)&clientAddr, &clientAddrLen);
        if (clientSocket == -1) {
            printf("Failed to accept client connection.\n");
            continue;
        }

        printf("Accepted client connection from %s:%d.\n", inet_ntoa(clientAddr.sin_addr), ntohs(clientAddr.sin_port));

        // 處理客戶端請求
        handleClient(clientSocket);
    }

    close(serverSocket);
    return 0;
}

這個示例代碼創建了一個簡單的服務器，監聽8888端口。當有客戶端連接時，會接收客戶端發送的消息，并打印出來。然后可以根據具體需求進行處理，最后發送響應給客戶端。

需要注意的是，在實際的應用中，可能還需要添加一些安全性和穩定性的處理，比如使用SSL/TLS加密連接，處理多線程并發等。這只是一個簡單的示例，具體實現還需要根據實際需求進行調整和完善。