Linux C打印IP地址信息

#include <stdio.h>
#include <netdb.h>
#include <sys/socket.h>
#include <arpa/inet.h>

//由文件描述符打印对应IP地址和端口
void PrintAddrByFd(int sockfd)
{
struct sockaddr_in addr_in;
socklen_t len = sizeof(addr_in);
getsockname(sockfd, (struct sockaddr *)&addr_in, &len);
if (addr_in.sin_family != AF_INET) {
printf("Not an Internet socket.\n");
return;
}
printf("addr:%s, port:%d\n", inet_ntoa(addr_in.sin_addr), ntohs(addr_in.sin_port));
}

#include <stdio.h>
#include <ifaddrs.h>
#include <netinet/in.h>

//打印本机所有IP地址
int main (int argc, const char * argv[])
{
struct ifaddrs * ifAddrStruct = NULL;
void * tmpAddrPtr = NULL;

getifaddrs(&ifAddrStruct);

while (ifAddrStruct != NULL)
{
if (ifAddrStruct->ifa_addr->sa_family == AF_INET)
{   // check it is IP4
// is a valid IP4 Address
tmpAddrPtr = &((struct sockaddr_in *)ifAddrStruct->ifa_addr)->sin_addr;
char addressBuffer[INET_ADDRSTRLEN];
inet_ntop(AF_INET, tmpAddrPtr, addressBuffer, INET_ADDRSTRLEN);
printf("%s IPV4 Address %s\n", ifAddrStruct->ifa_name, addressBuffer);
}
else if (ifAddrStruct->ifa_addr->sa_family == AF_INET6)
{   // check it is IP6
// is a valid IP6 Address
tmpAddrPtr=&((struct sockaddr_in *)ifAddrStruct->ifa_addr)->sin_addr;
char addressBuffer[INET6_ADDRSTRLEN];
inet_ntop(AF_INET6, tmpAddrPtr, addressBuffer, INET6_ADDRSTRLEN);
printf("%s IPV6 Address %s\n", ifAddrStruct->ifa_name, addressBuffer);
}
ifAddrStruct = ifAddrStruct->ifa_next;
}
return 0;
}