How to avoid user second client you exe file

[roger5089]

Dear all
does any function code i can use in c++ programmer
to avoid user second time to client you exe file

[Brenton S.]

I really don't understand the question. Can you be more clear?

[VladimirF]

Dear all
does any function code i can use in c++ programmer
to avoid user second time to client you exe file
Is this what you are asking?
How can I limit my application to one instance?
(http://www.codeguru.com/forum/showthread.php?t=312467)

[roger5089]

Yes something like that , but i donot know why when i edit that code into my program it will can make other Instance


//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
AnsiString me;
AnsiString change;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{



}

int TForm1::InitInstance()
{
HANDLE mutex = CreateMutex(NULL, false, "TForm1");
DWORD error = GetLastError();
if(error == ERROR_ALREADY_EXISTS && mutex!=NULL ){

HANDLE TheSame;
if( (TheSame=FindWindow("TForm1","Form1"))!=NULL ){

PostMessage(
TheSame, // handle of destination window
0x1700, // message to send
0, // first message parameter
0 // second message parameter
);
}

}
return 0;
}
//---------------------------------------------------------------------------

void __fastcall TForm1::FormShow(TObject *Sender)
{
me = "this is roger";
Memo1->Lines->Text = me;
TForm1::InitInstance();
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Memo1Change(TObject *Sender)
{

change = Memo1->Lines->Text;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
ShowMessage(change);
// MessageBox(NULL,"TEXT",change,MB_OK);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
exit(8);
}
//---------------------------------------------------------------------------

[humptydumpty]

Did u mean that user can't create second instance of your application. if yes Simply uSe Singelton Class Concept. So user can't create more then One instance of your Application.

Thanx.