c - SO_KEEPALIVE : Set on the server socket or on a per-client basis?

Question

我有以下用于为套接字配置 TCP Keepalive 的函数:

int configure_tcp_keepalive(int fd)
{
    int opt_val = 1;
    if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &opt_val, sizeof(opt_val)) == -1)
        return -1;

    int keepcnt = 9; //default value on Linux
    if (setsockopt(fd, SOL_TCP, TCP_KEEPCNT, &keepcnt, sizeof(keepcnt)) == -1) 
        return -1;

    int keepidle = 30;
    if (setsockopt(fd, SOL_TCP, TCP_KEEPIDLE, &keepidle, sizeof(keepidle)) == -1) 
        return -1;

    int keepintvl = 30;
    if (setsockopt(fd, SOL_TCP, TCP_KEEPINTVL, &keepintvl, sizeof(keepintvl)) == -1) 
        return -1;
}

如果我在服务器 fd 上调用这个函数，它会影响每个 accept() 的客户端吗(即 accept() 的客户端会继承这些套接字选项，从而为 TCP Keepalive 配置)？我宁愿不必为每个客户端调用此函数，以最大程度地减少开销。谢谢。

Answer 1

看起来这应该可行。 《Unix网络编程》一书说: