如果我需要獲取IP的主機名,我應該使用哪個端口? getnameinfo()從哪裏獲取主機名?sin_port in sockaddr_in
struct sockaddr_in sa;
sa.sin_family = AF_INET;
sa.sin_port = htons(?); // which port ?
inet_pton(AF_INET, "x.x.x.x", &(sa.sin_addr));
char host[NI_MAXHOST];
getnameinfo((struct sockaddr *)&sa, sizeof(sa), host, NI_MAXHOST, NULL, 0, NI_NAMEREQD);
puts(host);