🚀 go-pugleaf

"Vladimir Stefanovic" <antivari@ptt.yu> wrote in message
news:41230302$1@newsgroups.borland.com...

>    void __fastcall TForm1::SendButtonClick(TObject *Sender)
>    {
>       if ( ClientSocket1->Active == true )
>          ClientSocket1->Close();
>       ClientSocket1->Address="128.128.129.162";
>       ClientSocket1->Open();
>       ClientSocket1->Socket->SendText( "Test!" );
>    }

In non-blocking mode, you can't send data until the TClientSocket's
OnConnect event has been triggered, which won't happen in that code example
because non-blocking sockets require a message queue for triggering socket
events.  Calling Open() posts a message to the message queue to trigger the
OnConnect event at a later time, which you have to wait for before then
sending your data.  For example:

    void __fastcall TForm1::SendButtonClick(TObject *Sender)
    {
        if ( ClientSocket1->Active )
            ClientSocket1->Close();
        ClientSocket1->Address="128.128.129.162";
        ClientSocket1->Open();
    }

    void __fastcall TForm1::ClientSocket1Connect(TObject *Sender,
TCustomWinSocket *Socket)
    {
        Socket->SendText( "Test!" );
    }

> CASE 3: (Works on second and all other
> SendButton clicks, but fails on first click ?!

You probably just aren't calling ProcessMessages() often enough.  You would
have to keep calling it until the socket actually finishes connecting, ie:

    void __fastcall TForm1::SendButtonClick(TObject *Sender)
    {
        if ( ClientSocket1->Active )
            ClientSocket1->Close();
        ClientSocket1->Address="128.128.129.162";
        ClientSocket1->Open();
        while( !ClientSocket1->Socket->Connected )    // <-- added this
            Application->ProcessMessages();
        ClientSocket1->Socket->SendText( "Test!" );
    }

> Why all this works in Blocking mode and not in NonBlocking?

Because you are not taking message handling into account properly.  Blocking
mode does not use messages at all.


Gambit