🚀 go-pugleaf

Sorry to continue this thread.

"Remy Lebeau [TeamB]" <gambit47_no_spam@yahoo_no_spam.com> wrote in message
news:414916f7$1@newsgroups.borland.com...
>
> You are misusing the COPYDATASTRUCT structure.

disagree.

> You should not be using the dwData value that way.  Yes, it is an
arbitrary 32-bit
> application-defined value - however - it is commonly used as a unique
identifer instead.
> WM_COPYDATA is so commonly used, even by the VCL itself,

I have not seen the VCL using WM_COPYDATA for intreproc.communications; I
don't mean
it does not.

> that you should assign your own unique value to dwData to help
differentiate between your
> own WM_COPYDATA messages and those that are actually meant for other
windows,

that's what WPARAM of WM_COPYDATA is for.

> which you should ignore.  If you need to specify how many strings are in
the data, then you should allocate some extra memory and put the count
inside the data itself instead of in the dwData value.
> ...
>     AnsiString s;
>     s.SetLength(Msg.CopyDataStruct->cbData);

You can not do this with BCB3: the SetLength method can only thruncate a
string.

>     ::CopyMemory(s.c_str(), Msg.CopyDataStruct->lpData,
Msg.CopyDataStruct->cbData);
>
> Alternatively:
>
>     AnsiString s((char*)Msg.CopyDataStruct->lpData,
Msg.CopyDataStruct->cbData);

The WM_COPYDATA message description insists I make a copy of the buffer
first.

Boba