Remove trailing spaces from a file using Windows batch?

Question

How could I trim all trailing spaces from a text file using the Windows command prompt?

Answer 1

I use this Python 2 script to print lines with trailing whitespace and remove them manually:

#!/usr/bin/env python2
import sys

if not sys.argv[1:]:
  sys.exit('usage: whitespace.py ')

for no, line in enumerate(open(sys.argv[1], 'rb').read().splitlines()):
  if line.endswith(' '):
    print no+1, line

I know that Python is not preinstalled for Windows, but at least it works cross-platform.