[Python-Dev] Remaining decisions on PEP 471 -- os.scandir()

Tim Delaney timothy.c.delaney at gmail.com
Mon Jul 14 02:52:42 CEST 2014

On 14 July 2014 10:33, Ben Hoyt <benhoyt at gmail.com> wrote:


If we go with Victor's link-following .is_dir() and .is_file(), then
> we probably need to add his suggestion of a follow_symlinks=False
> parameter (defaults to True). Either that or you have to say
> "stat.S_ISDIR(entry.lstat().st_mode)" instead, which is a little bit
> less nice.

Absolutely agreed that follow_symlinks is the way to go, disagree on the
default value.

> Given the above arguments for symlink-following is_dir()/is_file()
> methods (have I missed any, Victor?), what do others think?

I would say whichever way you go, someone will assume the opposite. IMO not
following symlinks by default is safer. If you follow symlinks by default
then everyone has the following issues:

1. Crossing filesystems (including onto network filesystems);

2. Recursive directory structures (symlink to a parent directory);

3. Symlinks to non-existent files/directories;

4. Symlink to an absolutely huge directory somewhere else (very annoying if
you just wanted to do a directory sizer ...).

If follow_symlinks=False by default, only those who opt-in have to deal
with the above.

Tim Delaney
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-dev/attachments/20140714/c4d51625/attachment.html>

More information about the Python-Dev mailing list