[Tutor] try and file existence

[Steven D'Aprano]

On Sat, Aug 15, 2015 at 02:24:21PM -0500, boB Stepp wrote:
> On Fri, Aug 14, 2015 at 10:39 PM, Steven D'Aprano <steve at pearwood.info> wrote:

> > There is also os.path.exists(filename), but you should avoid using that
> > if possible. The problem is this:
> >
> > if os.path.exists(filename):
> >     # file exists *right now*
> >     # but a millisecond later, some other program deletes it...
> >     # and now it doesn't exist any more
> >     with open(filename) as f:  # gives an error
> >         ...
> 
> I understand your points, but wonder then what is the intended use for
> os.path.exists()?  That is, in what types of circumstances would it be
> both appropriate and safe to use?

def print_file_names(possible_names):
    print("List of file names checked")
    print("--------------------------"
    for name in possible_names:
        if os.path.exists(name):
            print(name)
        else:
            print("missing:", name)


-- 
Steve