Need expert advise: I need to retrieve Keithley's Measure Function (which could only be Current or Voltage) by polling the instrument.
Usually it is done with a command similar to this: smua.command.
However I checked the reference guide and there is no such a command to get this info.
You've posted to a board for NI DMM's - not a place for instrument specific questions. For this sort of question, you should be asking Keithley if you can't find the answer yourself in the manual.
No idea why you would ask this in a NI forum instead of the keithley one.
The forum is for NI DMMs and _Precision DC Sources_, which is the Keithley SMU. I've asked Keithley but have not gotted the response yet.
When I don't understand a particular device's syntax, I'll take a look at the LabVIEW instrument driver, if it exists (2602 located here), and see what they're doing. Of course, a lot of these APIs just call into a DLL, but usually there's some helpful knowledge in the code. Then you can just port the call over to an equivalent text-based syntax. Hope this helps.