DNS.c

//DNS (Domain Name System) client server to resolve the given hostname
#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<errno.h>
#include<sys/socket.h>
#include<netdb.h>
#include<netinet/in.h>
#include<arpa/inet.h>

int main(int argc,char* argv[])
{
	struct hostent* hen;
	struct in_addr** addr_list;
	
	if(argc!=2)
	{
		printf("Usage: <Hostname>");
		return 0;
	}
	
	hen=gethostbyname(argv[1]);
	if(hen==NULL)
	{
		herror("gethostbyname");
		exit(1);
	}
	
	printf("Hostname: %s\n",hen->h_name);
	addr_list=(struct in_addr**)hen->h_addr_list;
	for(int i=0;addr_list[i]!=NULL;i++)
	{
		printf("IP Address: %s\n",inet_ntoa(*addr_list[i]));
	}
	return 0;
}