Getting information on system

I started a new thread on this since it is a very different question from the one about environment variables. What I need is an array that stores as much information about what's going on with the computer as possible. I can design a different version for every Windows OS, but the information needs to be of the same format for every computer running that OS. What information can I get, and how can I get it? I've tried environment variables, and not only would their information be quite useless (as they might as well be constants), but there are some variables there when they aren't at other times, and I need the format to remain pretty constant.

Not sure what you're really after but GetVersionEx will give you the name,rank and serial number of each windows os which will enable you to make runtime decisions about os specific stuff, right down to version number/service packs.

Other information gathering api's include:
GetSystemMetrics
GetSystemInfo.
SystemParametersInfo.
GetSysColor.

You may want to take a look at registry functions, too.

I've been going over my algorithm, and I think I may have figured out a way that I can handle different variables every time. I'm not interested in finding out what OS the users running, because that might as well be a constant. I'd like to now things like the number of programs running, a list of programs running, how to CPU's running, thing's like that. I was told about using ::. Can I get the output of that read to my program instead of striaght to output?

I'm sorry, I should've figured this out in the original thread. :: won't work in C++, it's an operator for classes. They must've meant C. Any alternatives?