I contacted my sales engineer.  I was told they are checking if https://cedocs.intersystems.com/latest/csp/docbook/Doc.View.cls?KEY=GBCP... will be carried out to iris.  So I would rather not close this thread as an accepted answer.

A lot of my applications use this method, if IRIS doesn't support it any more, at least, I wish they can provide another C++ method.

Jon,

Yes, I took windows' cache 2017's odbc library and run the code again iris 2020.1 using your example, it works.

Now the question is if I can continue using my code compiled with cache 2017 for iris?

I don't know docker almost.  It is hard to follow your example.  I don't know how to install g++, vim, make on the docker container.  So I gave up.  But you indeed gave me light.

Thanks a lot!

Thank you so much!  I will study your reply and get back to you.

What does SIP  stand for?  Thanks.

With Cache, cpp can be used to access databases on a different machine.  If callin doesn't allow that, then iris callin is not a replacement of cache cpp.  So our c++ program will not be able to be upgraded with IRIS.

I made it work and realized callin has no way to connect to iris on a different machine?

am I wrong?  I hope so.

Thank you!

Where can I find c++ callin examples?

 Thanks,

This works like a charm!!!!!!!!!!!!

Thank you!!!!