memory model: are far and huge pointers still relevant?

[Wolfgang]

Hi,

importing functions provided by an external DLL I was wondering about some of the function declarations using the far or huge keyword, e.g. double far *cntr or unsigned long HUGE *datp . I thought that these memory models were useful (or even necessary) for 16 bit programs, but do I still need to specify a pointer as large or huge in todays 32 bit programs, i.e. using the CVI compiler?

Thanks, Wolfgang 

[Wolfgang]

hm, let's try again in the new year 🙂

If the question was unclear:

do I need to declare a function as double far *cntr or is it safe to omit the keywords 'far', 'huge' etc.

Thanks, Wolfgang

[Guillaume Dargaud]

My memory is hazy... aren't 'far' and 'huge' old 16-bit code, long gone and
forgotten ?
--
Guillaume Dargaud
http://www.gdargaud.net/

[Wolfgang]

Hi Guillaume,

that's what I thought, too... but now I have to use a hardware driver (obviously an old one) where the functions are declared this way and I wanted to know if I can ignore these key words or not...

Thanks, Wolfgang

[UM · Accepted solution]

Hi Wolfgang,

attached you’ll find a link, which describes, how to use the mentioned data types in CVI.
What is "Thunking" and How Does it Affect CVI's 32-bit Environment?
http://digital.ni.com/public.nsf/allkb/F72A410523887C97862562BD007994C7?OpenDocument

Ulrich
AE-NICER

[Wolfgang]

Hi Ulrich,

Thanks a lot for addressing this question! I was afraid that it might have been too trivial, after following your link it seems to me that it might be too difficult to solve... But I'll try and will contact the company distributing the hardware and the driver DLL...

Best wishes,

Wolfgang

[Wolfgang]

If I may just add a suggestion for your knowledgebase article: adding some of the keywords 'far', 'near', 'huge' might increase its visibility... I was searching before asking in the forum, but wasn't aware of the word 'thunking'..

Wolfgang