Ed,

Nice chat. Thanks for the feedback.

>Kenneth,
>
>>>As far as speed, the library itself is fast, but VisFox is faster at native functions.
>>
>>IOW, the equivalent of a simple statement, such as COPY TO FOR..., is slower in the C++ implementation than the same command in VisFox? Or does this apply only to situations where you are calling in the loop?
>
>That's right. simple statements that work in VisFox (IME) run as fast as anything I've coded in codebase. Of course, I've had to right a few codebase routines where there is no VisFox equiv, and they still work fast.
>
>>This is interesting that you say this. In beginning my experiments, I wrote a little dummy routine in C++ that would loop a few times and return, then built a DLL.
>
>The reason I needed the FLL was so codebase could enter data into the current VisFox work area. Of course with a DLL you don't have VisFox work area access, so you're right, a straight DLL call will be *Much* faster than an FLL call, since it doesn't have to access VFP work areas or variables.
>
>It seems since you won't be using VisFox at all, you can just write the DLL's and call them from whatever language you're using and get excellent speed.
>
>-Ed
>
>
>>Ed,
>>
>>So:
>>
>>>As far as speed, the library itself is fast, but VisFox is faster at native functions.
>>
>>IOW, the equivalent of a simple statement, such as COPY TO FOR..., is slower in the C++ implementation than the same command in VisFox? Or does this apply only to situations where you are calling in the loop?
>>
>>>> If you are planning on writing a FLL, try not the leave the library until all processing is done.
>>
>>Actually, the need is more for an engine than a library, something that does a specific set of tasks. I don't see mixing native VFP and DLL calls. But the warning is well taken.
>>
>>>> The switching between FLL library and VisFox code is very expensive. As long as the loop runs inside the C++ FLL it will be fast.
>>
>>This is interesting that you say this. In beginning my experiments, I wrote a little dummy routine in C++ that would loop a few times and return, then built a DLL. I found that putting a call to this DLL inside a Fox loop like the following:
>>
>>

>>FOR k = 1 TO 100000
>>  =MyDLLCall()
>>ENDFOR
>>

>>
>>could execute as fast as any other loop that did not involve a disk access, but that it slowed way down when I put a call into any optimizable expression, such as:
>>
>>

>>COPY TO... FOR (My Optimizable Expression) AND MyDLLCall()
>>

>>
>>The COPY TO runs at standard VFP speeds without the DLL call, but slows down by a factor of 10 with the DLL call.
>>
>>Do you think there is a difference between the FLL and the DLL that could be causing you to see the expensive call? Are you attempting calls inside optimizable commands?
>>
>>Thanks for the reply.