Question

I have a singleton class, and I will compile it as a library static(lib) or dynamic(dll).

Is it guaranteed that calls to same file in a machine always refer to same and unique instance in both cases?

Edit:
What if a process loads two different library and different functions from these libraries want to use instance of singleton class. Now, they are accessing same instance, am I right?

Thanks,

Answer 1

No, different processes will not share a singleton from a common library. Different processes use different memory spaces, so each will instantiate its own singleton.

You’ll need to use some sort of shared memory or interprocess-communication to share data between processes.

If a single process loads libraries A and B, and both those libraries use a singleton from library C, then they will be using the same instance.