cloud_sum_server

void cloud_sum(int sockfd)
{
    ssize_t n;
    char buf[MAXLINE];
    long a = 0, b = 0;
again:
    while ( (n = read(sockfd, buf, MAXLINE)) > 0){
        if (sscanf(buf, "%ld %ld", &a, &b) > 0)
            snprintf(buf, sizeof(buf), "%ld\n", a + b);
        else
            snprintf(buf, sizeof(buf), "input error\n");
    
        n = strlen(buf);
        write(sockfd, buf, n);
        fputs(buf, stdout);
        bzero(buf, sizeof(char) * MAXLINE);
    }

    if (n < 0 && EINTR == errno)
        goto again;
    else if (n < 0)
        cout<<"read error!"<<endl;
    else if (0 == n)
        cout<<"EOF"<<endl;
}