If I want to use 64-bit C-Visa do I link to the Visa64.dll or the Visa32.dll? Both are in the system32 dir on a 64-bit O/S. They are both provided by IVI.
Whats the difference between these 2 Dll's. Using dependency walker I see they both have the standard VISA API exported but the Visa64.dll depends on other Dll's like: VisaConfigMgr.dll and VisaUtilites.dll where as the Visa32.dll doesn't depend on any other Dlls.
Answer by Ted Wang · Dec 13, 2016 at 09:24 PM
You can link to either. The visa32.dll on 64-bit's system32 directory contains entry points that are simply forwarders to the respective visa64.dll entry points. It was created so that users may use the same library name for both 32-bit and 64-bit applications. Here's a snippet of the module definition file:
EXPORTS viGetDefaultRM = visa64.viGetDefaultRM @128 viOpenDefaultRM = visa64.viOpenDefaultRM @141 ...