<p>I need a way to determine the space remaining on a disk volume using python on linux, Windows and OS X. I'm currently parsing the output of the various system calls (df, dir) to accomplish this - is there a better way?</p>

The
os.statvfs()
function is a better way to get that information for Unix-like platforms (including OS X). The Python documentation says "Availability: Unix" but it's worth checking whether it works on Windows too in your build of Python (ie. the docs might not be up to date).
Otherwise, you can use the
pywin32
library to directly call the
GetDiskFreeSpaceEx
function.