How to avoid Python fileinput buffering [duplicate]

Answer 1

Have you tried:

def hook_nobuf(filename, mode):
    return open(filename, mode, 0)

fi = fileinput.FileInput(openhook=hook_nobuf)

Not tested it, but from reading what openhook param does and what passing 0 to open for bufsize param, this should do the trick.

Answer 2

Try running python -u; man says that it will "force stdin, stdout and stderr to be totally unbuffered".

You can just alter the hashbang path at the first line of filter.py.