Linux下C语言实现“域名“转“ip“

原文http://www.360doc.com/content/14/0514/11/1123425_377486376.shtml
#include

#include

int main(int argc, char** argv)

{

assert(argc == 2);

const char* hostname = argv[1];

struct hostent* host;

host = gethostbyname(hostname);

if (NULL == host)

{

perror("can not get host by hostname");

exit(EXIT_FAILURE);

}

printf("host ip=%s\n", inet_ntoa(*((struct in_addr*)host->h_addr)));

return EXIT_SUCCESS;

}

本人文峰聊书斋在centos6平台验证
[root@www ble_mesh]# ./a.out www.baidu.com
host ip=14.215.177.38
[root@www ble_mesh]#
文峰聊书斋另外加入：
#define SOCKADDR_IN(addr, ip, port) do{ \
                                memset(&(addr), 0, sizeof(addr)); \
                                (addr).sin_family      = AF_INET;     \
                                (addr).sin_addr.s_addr = inet_addr(ip);   \
                                (addr).sin_port        = htons(port);     \
                                if ((addr).sin_addr.s_addr == INADDR_NONE){    \
                                    struct hostent* pHost = gethostbyname(ip); \
                                    if (pHost == NULL){return ;} \
                                    memcpy(&(addr).sin_addr, pHost->h_addr_list[0], pHost->h_length);} \
                                }while(0)

    struct sockaddr_in servaddr;
   SOCKADDR_IN(servaddr,"www.baidu.com", 5000);
    //SOCKADDR_IN(servaddr,"192.168.0.11", 5000);
   printf("baidu%s\n",inet_ntoa(servaddr.sin_addr));