Search code examples
windowsdelphiwinapihandlewindow-handles

How to get count of opened handles that belongs to a certain process?


You can use the program Process Explorer to see how many handles running applications have. Is there a way with Delphi code to get this number? I am interested in tracking the number for the application itself; not to find the number of handles used by other applications as Process Explorer is doing.

My intention is for the application to track/detect possible resource leaks.


Solution

  • Use the GetProcessHandleCount function. This API function is in recent versions of Delphi imported by the Winapi.Windows unit (so you can omit the presented one):

    function GetProcessHandleCount(hProcess: THandle; var pdwHandleCount: DWORD): BOOL; stdcall;
      external 'kernel32.dll';
    
    procedure TForm1.Button1Click(Sender: TObject);
    var
      HandleCount: DWORD;
    begin
      if GetProcessHandleCount(GetCurrentProcess, HandleCount) then
        ShowMessage('Handle count: ' + IntToStr(HandleCount));
    end;