If you see bash related problem solutions coming equally from Stack Overflow, Unix & Linux, Ask Ubuntu, Super User and Server Fault, and they seem to be on-topic at all those sites, then my recommendation would be to:
- Choose from amongst them the site with whose community you most identify
- Double check their On Topic page against the question you are about to ask
- If it seems to be on-topic, then ask the question on that site
If it gets closed for being off-topic then you will have learned more about that site and what it considers to be on-topic, and can look at instead posting that question to the community with which you identify secondmost.
I refer to bash above but this advice "can be generalised to other programming related questions that go for managing an operating system via scripting or programming language that is kinda cross platform".