在C中从客户端向服务器发送多个答复

Question

My server sends me the following message:

INFO 123456\\n (number may vary)

I am supposed to respond to the server with:

REPLY 123456\\n - matching reply

Currently, my code is correctly sending one reply. However, the server is returning with an error when I try to send a second reply. I feel like it may have something to do with the reply_message char array? Any thoughts on this? I posted my code below. Thanks!

        while(1) {
        server_reply[0] = '\0';
        printf("Server Reply: %s\n", server_reply);
        n = recv(sockfd, server_reply, sizeof(server_reply), 0);
        if (n <= 0) {
            printf("Receive failed\n");
            return 1;
        }
        printf("Message Recieved from Server: %s\n", server_reply);

        if (server_reply) {
            char checkInfo[5];
            memcpy(checkInfo, &server_reply, 4);
            checkInfo[4] = '\0';

            if (strcmp(checkInfo, "INFO") == 0) {
                char reply_message[sizeof(server_reply) + 1];
                memset(reply_message, 0, sizeof(reply_message));
                strncpy(reply_message, "REPLY ", sizeof reply_message - 1);
                char *replyNumber = server_reply;
                replyNumber++;
                replyNumber++;
                replyNumber++;
                replyNumber++;
                replyNumber++;
                strcat(reply_message, replyNumber);
                strcat(reply_message, "\n");
                printf("Reply Message: %s\n", reply_message);

                if ((send(sockfd, reply_message, strlen(reply_message), 0)) < 0) {
                    printf("Send failed");
                    close(sockfd);
                    return 1;
                }
                printf("Message Sent: %s\n", reply_message);
                reply_message[0] = '\0';
            }
        }
    }

I also posted the error I'm receiving.

Answer 1

It is understood from the above code

"server_reply[0] = '\\0';"

server_reply is an array or a character pointer. While doing

"memcpy(checkInfo, &server_reply, 4);"

there is no need of "&".