struct hostent * hostEnt;
hostEnt = gethostbyname("www.google.com");

struct hostent {
        char    *h_name;        /* official name of host */
        char    **h_aliases;    /* alias list */
        int     h_addrtype;     /* host address type */
        int     h_length;       /* length of address */
        char    **h_addr_list;  /* list of addresses */
}

#include<stdlib.h>

main()
{
      char *hostname;
      struct hostent * ip;
      printf("*** Hostname To IP Resolver ***\n\nHostname: ");
      scanf("%s",&hostname);
      ip = gethostbyname(hostname);
      printf("\n\nIP: %s",ip);
      system("pause>nul");
      return(0);
}

#pragma comment( lib, "ws2_32.lib" )
#include <winsock.h>
#include <stdio.h>

int main(void)
{
    WORD wVersionRequested; 
    WSADATA wsaData;
    SOCKADDR_IN SockAddr;

    wVersionRequested = MAKEWORD (1,1);
    if(WSAStartup(wVersionRequested , &wsaData) != 0)
    {
        printf("WSAStartup() Error! \n");
        return 1;
    }
    hostent* HostInfo = gethostbyname("www.google.com");
    memcpy(&(SockAddr.sin_addr),HostInfo->h_addr,HostInfo->h_length);
    char* pIP = inet_ntoa(SockAddr.sin_addr);
    printf("IP Address: %s\n", pIP);
    WSACleanup();
return 0;
}

#include<stdlib.h>
#include<winsock.h>

main()
{
      while(1)
      {
      char *hostname;
      struct hostent * ip;
      system("cls");
      printf("*** Hostname To IP Resolver ***\n\nHostname: ");
      scanf("%s",&hostname);
      ip = gethostbyname(hostname);
      printf("\n\nIP: %s\n",ip);
      system("pause>nul");
      }
      return(0);
}

Compiler: Default compiler
Building Makefile: "C:\Documents and Settings\Owner\Desktop\Makefile.win"
Executing  make...
make.exe -f "C:\Documents and Settings\Owner\Desktop\Makefile.win" all
gcc.exe -c main.c -o main.o -I"C:/Dev-Cpp/include"   

main.c: In function `main':
main.c:17: error: `hostent' undeclared (first use in this function)
main.c:17: error: (Each undeclared identifier is reported only once
main.c:17: error: for each function it appears in.)
main.c:17: error: `HostInfo' undeclared (first use in this function)

make.exe: *** [main.o] Error 1

Execution terminated

hostent* HostInfo;
char hostname[1024];
char *ip;
WSADATA wsaData;
SOCKADDR_IN SockAddr;

if(WSAStartup(MAKEWORD(1,1),&wsaData)!=0) {return 0;}
printf("*** Hostname To IP Resolver ***\n\n");
while(1)
      {
      printf("HOSTNAME:\t");
      scanf("%s",&hostname);
      HostInfo=gethostbyname(hostname);
      memcpy(&(SockAddr.sin_addr),HostInfo->h_addr,HostInfo->h_length);
      ip=inet_ntoa(SockAddr.sin_addr);
      printf("IP:\t\t%s\n\n",ip);
      }    
WSACleanup();
return 0;

#pragma comment( lib, "ws2_32.lib" )
#include <winsock.h>
#include <stdio.h>

void printError( CHAR *msg )
{
	DWORD eNum;
	CHAR sysMsg[256] = {0};
	CHAR* p;

	eNum = GetLastError( );
	FormatMessage( FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
		NULL, eNum,
		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), 
		sysMsg, 256, NULL );
	p = sysMsg;
	while( ( *p > 31 ) || ( *p == 9 ) )
		++p;
	do { *p-- = 0; } while( ( p >= sysMsg ) &&
		( ( *p == '.' ) || ( *p < 33 ) ) );

	printf( "ERROR: %s failed with error %d (%s)\n", msg, eNum, sysMsg );
}

int main(void)
{
	WORD wVersionRequested; 
	WSADATA wsaData;
	SOCKADDR_IN SockAddr;
	hostent* HostInfo = NULL; 

	wVersionRequested = MAKEWORD (1,1);
	if(WSAStartup(wVersionRequested , &wsaData) != 0)
	{
		printError( "WSAStartup" );
		return 1;
	}
	HostInfo = gethostbyname("www.google.com");
	if (HostInfo == NULL)
	{
		printError("gethostbyname");
	}
	else
	{ 
		memcpy(&(SockAddr.sin_addr),HostInfo->h_addr,HostInfo->h_length);
		CHAR* pIP = inet_ntoa(SockAddr.sin_addr);
		printf("IP Address: %s\n", pIP);
	}
	WSACleanup();
	return 0;
}

#include <stdio.h>
#include <winsock.h>

int main (int argc, char** argv)
{
	struct sockaddr_in addr;
	struct hostent* h;
	char  buffer[BUFSIZ];
	char* tmp;
	WSADATA wsaData;

	if (WSAStartup(MAKEWORD(1, 1), &wsaData)) {
		fprintf(stderr, "Error: WSAStartup failed.\n");
		return 1;
	}
	if (argc == 1) {
		printf("host: ");
		fgets(buffer, sizeof(buffer), stdin);
		if ((tmp = strchr(buffer, '\n')) != NULL)
			*tmp = '\0';
		h = gethostbyname(buffer);
	}
	else {
		h = gethostbyname(argv[1]);
	}
	if (h == NULL) {
		//herror("Error: gethostbyname");
		fprintf(stderr, "Error: gethosbyname() failed.\n");
		WSACleanup();
		return 1;
	}
	addr.sin_addr = *(struct in_addr*) h->h_addr;
	printf("ip: %s", inet_ntoa(addr.sin_addr));

	WSACleanup();
	return 0;
}