问 C/C++ getnameinfo ai_family不支持macOS

EN

如果macOS或某些虚拟接口可用，下面的代码将不再在IPv6上工作。

我总是得到错误的 getnameinfo() failed: Unknown error (ai_family not supported)

你知道这有什么不对吗？我只需要一个正确的网络接口与ipv4和互联网。

这个问题首先出现在macOS Sierra身上。

#include "jni.h"
#include "bla_nativeclasses_JNISubNetMask.h"
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netdb.h>
#include <ifaddrs.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
static jobjectArray make_row(JNIEnv *env, jsize count, const char* elements[])
    jclass stringClass = (*env)->FindClass(env, "java/lang/String");
    jobjectArray row = (*env)->NewObjectArray(env, count, stringClass, 0);
    jsize i;
    for (i = 0; i < count; ++i) {
        (*env)->SetObjectArrayElement(env, row, i, (*env)->NewStringUTF(env, elements[i]));
    return row;
JNIEXPORT jobjectArray JNICALL Java_bla_JNISubNetMask_getSubNetMask(JNIEnv *env, jobject jobj){
    struct ifaddrs *ifaddr, *ifa;
    int family, s ,s2;
    int i = 0;
    int count = 0;
    char host[NI_MAXHOST];
    char subnet[NI_MAXHOST];
    char *tmp = NULL;
    const char* net[1000];
    if (getifaddrs(&ifaddr) == -1) {
        perror("getifaddrs");
        exit(EXIT_FAILURE);
    /* Walk through linked list, maintaining head pointer so we can free list later */
    for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
        if (ifa->ifa_addr == NULL)
           continue;
        if (ifa->ifa_addr->sa_family != AF_INET)
            continue;
        s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in), host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
        s2 = getnameinfo(ifa->ifa_netmask, sizeof(struct sockaddr_in), subnet, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
        if (s != 0 || s2 != 0) {
            printf("getnameinfo() failed: %s (%s)\n", gai_strerror(s), gai_strerror(s2));
            exit(EXIT_FAILURE);
        tmp = (char *)malloc(100*sizeof(char));
        strcpy (tmp,ifa->ifa_name);
        net[i++] = tmp;
        tmp = (char *)malloc(100*sizeof(char));
        strcpy (tmp,host);
        net[i++] = tmp;
        tmp = (char *)malloc(100*sizeof(char));
        strcpy (tmp,subnet);
        net[i++] = tmp;