How to get the IP address of my computer 1

[SCervantes]

Hello,

Any clues on how to get the IP address of the computer that runs the code?

I am coding an application that should show the IP in its main window for user's information.

Thanks,
Sergio

 

[2ffat]

I've not done it but I'm told that you need to use the Windows APIs gethostname, gethostbyname, or GetAdapterInfo(). I did find one section of code that might help. It's by Michel Leunen (

http://www.leunen.com).

char host_name[64]; //holds the name
gethostname(host_name,sizeof(host_name));
hostent *he = gethostbyname(host_name);
in_addr aAddress;
memcpy(&address,he->h_addr_list[0],he->h_length);
char IP_address[64]; //holds the IP address
strcpy(IP_address,inet_ntoa(address));

James P. Cottingham
-----------------------------------------
^{To determine how long it will take to write and debug a program, take your best estimate, multiply that by two, add one, and convert to the next higher units.}

 

[stowelly]

if you use the fastnet components (any of the server ones etc)

its as simple as this

String Bob = NMGeneralServer->LocalIP;

 

[SCervantes]

Thanks, guys, for your help! Now my code is working all right! I tried both options and worked well.

Maybe the final code (by using Win API) is helpful to somebody else, so, it is below.

Thanks again,
Sergio


//----------------------------------------
// *** get locahost's name
char host_name[64];
struct hostent *datos_host;

// *** initialize the winsocket
WORD wVersionRequested;
WSADATA wsaData;
int err;

wVersionRequested = MAKEWORD( 2, 2 );

err = WSAStartup( wVersionRequested, &wsaData );
if ( err == 0 )
{
//*** check the winsock compatibility

if ( LOBYTE( wsaData.wVersion ) == 2 &&
HIBYTE( wsaData.wVersion ) == 2 )
{
/* The WinSock DLL is acceptable. Proceed. */

if( !gethostname(host_name,sizeof(host_name)))
{
//*** finally, I get the IP
struct hostent *he;
in_addr address;

if( he = gethostbyname(host_name))
{
memcpy( &address, he->h_addr_list[0]
, he->h_length);
char IP_address[64];
strcpy(IP_address,inet_ntoa(address));

//*** show hostname and its IP
MessageBox( AnsiString( host_name)
+ " - " + IP_address;
}
else
{
int i_error = WSAGetLastError();
ShowMessage( AnsiString( "¡Puff! - Error #")
+ i_error
+ " when running gethostbyname.");
}
}
else
{
ShowMessage( AnsiString( "Error #")
+ (int)WSAGetLastError()
+ " when running 'gethostname'.");
}

}
else
{
ShowMessage( "Unable to start the 'winsock'.");
}
}
else
{
WSACleanup( );
ShowMessage( "Can't find any compatible 'winsock'");
}
//----------------------------------------