Hi,

I have related question. I think I recall that calling someFunction(@tcLongString) is quicker than someFunction(tcString) if we don't make any changes with tcString inside the function.

Do I remember correctly and it's indeed better to use first syntax?

Thanks in advance.

>Does anybody have any experience passing parameters by reference to a DLL, with a DLL that uses SendMessage() to call back into the running VFP9 app?
>
>I think I've found a bug where if you do this, the initiating function loses its by-reference context and doesn't update the variables updated in the DLL upon return.
>
>Example flow:
>lcUpdateVar = SPACE(32)
>VFP9 calls some_function(@lcUpdateVar) in DLL
>some_function() issues SendMessage() to call back into the VFP9's _vfp.HWnd, to which a BINDEVENT() has been added to capture a particular message.
>VFP9's handler for that message does something and returns.
>some_function() goes to update lcUpdateVar with the text "Hi, mom!" and returns
>
>When VFP9 returns from some_function() and goes to the next VFP9 source code line, the value lcUpdateVar is not updated.
>
>If I disable the SendMessage() callback, it works.
>
>I'm wondering if anyone knows of this bug in VFP9? Or a way around it? I'm using _stdcall in the DLL and all parameters are aligning. It only seems to fail when I use SendMessage() to call back, making me think something in VFP9 is being altered to where it loses the by-ref parameter reference, and just ignores the return values when it comes back.