🚀 go-pugleaf

"JD" <nospam@nospam.com> wrote in message
news:40b0d61d$1@newsgroups.borland.com...

> I still get double notification with a single change using
> WaitForMultipleObjects and no notification at all if I use
> WaitForSingleObject (which does not error).

The following code works fine for me, and does not produce double
notifications at all:

    --- TMonitorThread.h ---

    #define APPWM_CHANGED (WM_APP+100)

    class TMonitorThread : public TThread
    {
    private:
        AnsiString FPath;
    protected:
        void __fastcall Execute();
    public:
        __fastcall TMonitorThread(const AnsiString &Path);
    };


    --- TMonitorThread.cpp ---

    __fastcall TMonitorThread::TMonitorThread(const AnsiString &Path)
        : TThread(true)
    {
        FPath = Path;
        Resume();
    }

    void __fastcall TMonitorThread::Execute()
    {
        HANDLE hFind = FindFirstChangeNotification(FPath.c_str(), FALSE,
FILE_NOTIFY_CHANGE_LAST_WRITE);
        if( hFind != INVALID_HANDLE_VALUE )
        {
            while( !Terminated )
            {
                switch( WaitForSingleObject(hFind, 500) )
                {
                    case WAIT_OBJECT_0:
                        PostMessage(Application->MainForm->Handle,
APPWM_CHANGED, 0, 0);
                        if( !FindNextChangeNotification(hFind) )
                            Terminate();
                        break;

                    case WAIT_TIMEOUT:
                        // keep waiting...
                        break;

                    default:
                        Terminate();
                        break;
                }
            }

            FindCloseChangeNotification(hFind);
        }
    }


    --- Unit1.cpp ---

    #include "TMonitorThread.h"

    TMonitorThread *Thread = NULL;

    __fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
    {
        Thread = new TMonitorThread("C:\\");
    }

    __fastcall TForm1::~TForm1()
    {
        Thread->Terminate();
        Thread->WaitFor();
        delete Thread;
    }

    void __fastcall TForm1::WndProc(TMessage &Message)
    {
        if( Message.Msg == APPWM_CHANGED )
            ShowMessage("changed");
        else
            TForm::WndProc(Message);
    }


Gambit