Why PI Acton Labview toolkit is not free but C++ SDK is free

[Jamiechuang]

Now i am using PI Acton Spectrapro 2300i.

and want to develop our software to control the system

but the company told us the C++ SDK is free

but the labview Toolkit is not free.

Why ,for i have owned the dlls about the system ,if i can call the dlls in the labview.So the labview should be also free.

Are three some problems when calling C++ in Labview,or need some driver when using Labview??

Thanks very much

[Wiebe@CARYA]

You should ask the supplier about why they charge for the LabVIEW toolkit
and not for the C++ SDK.

Calling C++ dlls is not easy from LabVIEW, unless the functions are exported
as c functions. The C++ naming convention is something LabVIEW cannot
understand. A C++ dll doesn't automatically mean it uses a C++ naming
convention, so you'll have to check. Open the dll in a call library node and
see if the names you'd expect are there. If they are available, and you
don't see strange signs like _, *, &, # or @ in the names, it's probably
easy to call from LabVIEW.

One way to deal with this is to make a C/C++ wrapper that does use C naming
so LabVIEW can understand it, but you can't do that in LabVIEW.

Regards,

Wiebe.

[Jamiechuang]

You mean function name is a problem??

[Wiebe@CARYA]

The problem is not just the names. C++ uses the names to determine the type
of each parameter. In C++ each parameter can be an entire class, and each
class is defined by the application itself (this explaination is probably
not very good, but it gives the picture). So the naming is only how the
problem shows. The real problem is that C (or LabVIEW) cannot call functions
with a C++ name, since those functions are only suitable for C++, C simply
doesn't know how to call them (and neither can LabVIEW)....

So the trick is to make a C++ program that exports the needed functions as C
function. Then LabVIEW can call them.

Regards,

Wiebe.