Cross-platform space remaining on volume using python

Question

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?

Answer 1

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.

Answer 2

I Don't know of any cross-platform way to achieve this, but maybe a good workaround for you would be to write a wrapper class that checks the operating system and uses the best method for each.

For Windows, there's the GetDiskFreeSpaceEx method in the win32 extensions.

Answer 3

You can use df as a cross-platform way. It is a part of GNU core utilities. These are the core utilities which are expected to exist on every operating system. However, they are not installed on Windows by default (Here, GetGnuWin32 comes in handy).

df is a command-line utility, therefore a wrapper required for scripting purposes. For example:

from subprocess import PIPE, Popen

def free_volume(filename):
    """Find amount of disk space available to the current user (in bytes) 
       on the file system containing filename."""
    stats = Popen(["df", "-Pk", filename], stdout=PIPE).communicate()[0]
    return int(stats.splitlines()[1].split()[3]) * 1024

Answer 4

If you dont like to add another dependency you can for windows use ctypes to call the win32 function call directly.

import ctypes

free_bytes = ctypes.c_ulonglong(0)

ctypes.windll.kernel32.GetDiskFreeSpaceExW(ctypes.c_wchar_p(u'c:\\'), None, None, ctypes.pointer(free_bytes))

if free_bytes.value == 0:
   print 'dont panic'

Answer 5

At last, complete cross-platform solution (use standard lib only):

import os
import platform
import ctypes

def get_free_space(folder):
    """ Return folder/drive free space (in bytes)
    """
    if platform.system() == 'Windows':
        free_bytes = ctypes.c_ulonglong(0)
        ctypes.windll.kernel32.GetDiskFreeSpaceExW(ctypes.c_wchar_p(folder), None, None, ctypes.pointer(free_bytes))
        return free_bytes.value
    else:
        return os.stavfs(folder).f_bfree