How to get Windows short file name in python?

You can use ctypes. According to the documentation on MSDN, GetShortPathName is in KERNEL32.DLL. Note that the real functions are GetShortPathNameW for wide (Unicode) characters and GetShortPathNameA for single-byte characters. Since wide characters are more general, we’ll use that version. First, set the prototype according to the documentation:

import ctypes
from ctypes import wintypes
_GetShortPathNameW = ctypes.windll.kernel32.GetShortPathNameW
_GetShortPathNameW.argtypes = [wintypes.LPCWSTR, wintypes.LPWSTR, wintypes.DWORD]
_GetShortPathNameW.restype = wintypes.DWORD

GetShortPathName is used by first calling it without a destination buffer. It will return the number of characters you need to make the destination buffer. You then call it again with a buffer of that size. If, due to a TOCTTOU problem, the return value is still larger, keep trying until you’ve got it right. So:

def get_short_path_name(long_name):
    """
    Gets the short path name of a given long path.
    http://stackoverflow.com/a/23598461/200291
    """
    output_buf_size = 0
    while True:
        output_buf = ctypes.create_unicode_buffer(output_buf_size)
        needed = _GetShortPathNameW(long_name, output_buf, output_buf_size)
        if output_buf_size >= needed:
            return output_buf.value
        else:
            output_buf_size = needed