There is a function gethostbyname for getting the ip address using
Winsock. This function will retrieve the ip address details into a variable of type "structure hostent".
The first step in creating this program is to ensure the socket library is initialized, if it is not initialized else-where.
The next step is to call the gethostbyname function which will return a pointer to the hostent structure. This pointer to
the hostent structure can be used to get the ip address into a sockaddr_in type.
In fact it is possible to get the ip without using the sockaddr_in structure also. But using sockaddr_in is a much cleaner
way of doing the work.
Please feel free to copy/paste the function below and use/manipulate it in your applications wherever needed.
#include <winsock2.h>
void GetHostIP()
{
char *Ip;
WSADATA wsaData;
struct hostent *pHostEnt;
struct sockaddr_in tmpSockAddr; //placeholder for the ip address
// Not needed if it is already taken care by some other part of the application
WSAStartup(MAKEWORD(2,0),&wsaData);
char hostname[25];
strcpy(hostname,"Test Computer
Name")
//This will retrieve the ip details and put it into pHostEnt structure
pHostEnt = gethostbyname(hostname);
if(pHostEnt == NULL)
{
printf("Error occured: %s\n",GetLastError());
return;
}
memcpy(&tmpSockAddr.sin_addr,pHostEnt->h_addr,pHostEnt->h_length);
Ip = NULL;
Ip = new char[17];
strcpy(Ip,inet_ntoa(tmpSockAddr.sin_addr));
printf("Ip Address of the machine %s is %s\n",Ip);
// Not needed if it is already taken care by some other part of the application
WSACleanup();
delete
[] Ip;
}
Note:
The socket programs in MFC need the library ws2_32.lib to be
referenced before linking. Otherwise the VC++ linker throws
errors.