Python change all files mode to read only. (excluding hidden files)

change_mod.py

#!/usr/bin/env python

"""
This script sets all files (excluding hidden ones) 
to read-only mode.
"""
from __future__ import print_function
import sys
import os
import glob
from subprocess import Popen

__author__ = "introom"
__email__  = "[email protected]"



def iter_files(path):
    """
    by default, this emits all files under `path` that are not hidden.
    aka., not starting with a .
    """
    # assert os.path.isdir(path)
    for fn in glob.glob(os.path.join(path, '*')):
        if os.path.isdir(fn):
            # oops, we are in py2 realm, no yield from (>= py3.3)
            for fn_ in iter_files(fn):
                yield fn_
        else:
            yield fn


def chmod(files_):
    for fn in files_:
        # XXX
        # It's bad, too much overheads for creating/destructing proc.
        # But who the heck cares?
        cmd = 'chmod -w {}'.format(fn)
        Popen(cmd, shell=True)


def main():
    argv = sys.argv
    if len(argv) != 2 or not os.path.isdir(argv[1]):
        print("please specify a valid directory. e.g., python chmod.py $MYDIR", file=sys.stderr)
        sys.exit(1)
    chmod(iter_files(argv[1]))


if __name__ == '__main__':
    main()