How do you find how much disk space is left in Cocoa?

Question

I suppose I'd like to be able to find out for any storage, not just the system disk, but that's most important.

Answer 1

Hard disk device manufacturers, use:

1GB = 1000MB

1MB = 1000 KB etc.

If you see a 8GB USB stick in Windows always shows less space than real (like 7,8 GB) because it is considered 1 GB = 1024 MB). In OSX the same USB stick is 8GB (real).

so (freeSpace / 1073741824) must be (freeSpace / 1000000000)

at least in OSX