以下是一个C++函数实现根据域名获取IPv6地址的示例：
#include <iostream>
#include <netdb.h>
#include <arpa/inet.h>
using namespace std;
bool get_ipv6_address(const char* domain_name, struct in6_addr& ipv6_address)
{
struct addrinfo hints;
struct addrinfo* result;
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_INET6; // 表示使用IPv6
int ret = getaddrinfo(domain_name, NULL, &hints, &result);
if (ret != 0) {
cerr << "getaddrinfo error: " << gai_strerror(ret) << endl;
return false;
}
for (struct addrinfo* rp = result; rp != NULL; rp = rp->ai_next) {
if (rp->ai_family == AF_INET6) {
memcpy(&ipv6_address, &((struct sockaddr_in6*)rp->ai_addr)->sin6_addr,
sizeof(struct in6_addr));
freeaddrinfo(result);
return true;
}
}
freeaddrinfo(result);
return false;
}
int main()
{
const char* domain_name = "www.google.com";
struct in6_addr ipv6_address;
bool success = get_ipv6_address(domain_name, ipv6_address);
if (success) {
char ip_str[INET6_ADDRSTRLEN];
inet_ntop(AF_INET6, &ipv6_address, ip_str, INET_ADDRSTRLEN);
cout << "The IPv6 address of " << domain_name << " is: " << ip_str << endl;
} else {
cout << "Failed to obtain the IPv4 address of " << domain_name << endl;
}
return 0;
}
该函数使用了getaddrinfo()函数来获取主机名对应的地址信息，其中传入的hints参数指定了使用IPv6地址。如果获取成功，则从结果中筛选出IPv6地址并返回给调用者。
注意，在实际使用过程中，可能需要根据不同的操作系统或编译环境进行一些适当的修改。
![#include
#include
#include
#include
#include
#include "sem_pv.h"
int main(void)
{
key_t key;
int pid,fd,semid,n;
char str[80];
key=ftok(".",5);
semid=sem_init(key);
fd=open("test.txt",O_...](https://linuxcpp.0voice.com/zb_users/upload/2023/05/202305162226144313964.png)
![#include
#include
#include
#include
#include
#include "sem_pv.h"
int main(void)
{
key_t key;
int pid,fd,semid,n;
char str[80];
key=ftok(".",5);
semid=sem_init(key);
fd=open("test.txt",O_...](https://linuxcpp.0voice.com/zb_users/upload/2023/05/202305162217558813401.png)
![#include
#include
#include
#include
#include
#include "sem_pv.h"
int main(void)
{
key_t key;
int pid,fd,semid,n;
char str[80];
key=ftok(".",5);
semid=sem_init(key);
fd=open("test.txt",O_...](https://linuxcpp.0voice.com/zb_users/upload/2023/05/202305162221011205155.png)
