我无法关闭服务器和客户端之间的套接字连接

Question

当我尝试关闭来自客户端的连接时遇到问题，我想在客户端写入“q”之类的字符串时关闭与服务器的连接，并且我在来自客户端的消息之后执行 strcmp由服务器读取，但由于未通过比较而无法正常工作。

这是服务器的代码

    while(1){

    if((n = read(newsocketfd,buffer,sizeof(buffer))) > 0)
            printf("(Mlength %d) message from Client:  %s\n",n,buffer);
    else{

        close(socketfd);
        close(newsocketfd);
        error("Error reading message \n");
    }

    if(strcmp("q",&buffer[n]) == 0)
        printf("El cliente intenta cerrar la conexión %s\n",&buffer[n]);
    else
        printf("Se recibieron datos desde el cliente %s\n",&buffer[n]);

    if(write(newsocketfd,response,255) > 0)
            printf("Writing response to Client socket \n");
    else
            error("Error writing message \n");
    }

return EXIT_SUCCESS;

}

这是客户端的代码

   do{
printf("Please, type your message: ");
bzero(buffer,256);
fgets(buffer,255,stdin);

n = write(socketfd,buffer,sizeof(buffer));
if(n < 0 )
    error("Error writing to socket \n");
else
    printf("...Message sent \n");

n = read(socketfd,buffer,sizeof(buffer));
if(n < 0 )
        error("Error writing to socket \n");
    else
        printf("\n Message from server: %s \n",buffer);

}while(strcmp("q",buffer)!=0);

Answer 1

read(newsocketfd, buffer, sizeof(buffer)))

缓冲区溢出-----------^

if ((n = read(newsocketfd, buffer, sizeof(buffer) - 1)) > 0) { /* Note -1 */
    buffer[n] = '\0'; /* read() doesn't add a trailing 0 */
    printf("(Mlength %d) message from Client:  %s\n",n,buffer);
} else {
    ...

---

if (strcmp("q", &buffer[n]) == 0) /* you are reading NUL ('\0') */

改为：

if (strcmp("q", buffer) == 0)