如何使用getifaddr()函数获取IPV6接口地址

Question

我有getifaddrs()定义,但它适用于IPv4.请指导我如何使用该getifaddrs()功能获取IPv6地址.

Answer 1

getifaddrs确实支持IPv6.以下是如何打印系统上所有接口的名称和IP地址的示例:

struct ifaddrs *ifa, *ifa_tmp;
char addr[50];

if (getifaddrs(&ifa) == -1) {
    perror("getifaddrs failed");
    exit(1);
}

ifa_tmp = ifa;
while (ifa_tmp) {
    if ((ifa_tmp->ifa_addr) && ((ifa_tmp->ifa_addr->sa_family == AF_INET) ||
                              (ifa_tmp->ifa_addr->sa_family == AF_INET6))) {
        if (ifa_tmp->ifa_addr->sa_family == AF_INET) {
            // create IPv4 string
            struct sockaddr_in *in = (struct sockaddr_in*) ifa_tmp->ifa_addr;
            inet_ntop(AF_INET, &in->sin_addr, addr, sizeof(addr));
        } else { // AF_INET6
            // create IPv6 string
            struct sockaddr_in6 *in6 = (struct sockaddr_in6*) ifa_tmp->ifa_addr;
            inet_ntop(AF_INET6, &in6->sin6_addr, addr, sizeof(addr));
        }
        printf("name = %s\n", ifa_tmp->ifa_name);
        printf("addr = %s\n", addr);
    }
    ifa_tmp = ifa_tmp->ifa_next;
}