You probably would need to write a C++ extension, make some OS API calls (good luck with that) through there, and propagate that data back to sourcemod where sourcepawn can catch it.
But unless you're writing a big portion of your code in C++ (and by big, I mean almost all of it, with sourcepawn only acting as a glue between the server and extension), I don't see why you need to know that information (especially if it's for tf2bwr or MvT, which makes it all the more bizarre).