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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Sat, 2 Mar 2013 10:58:12 -0700
Subject: Re: Dealing with exceptions
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Xref: csiph.com comp.lang.python:40349

On Sat, Mar 2, 2013 at 10:40 AM, bvdp <bob@mellowood.ca> wrote:
> Every time I write a program with exception handling (and I suppose that =
includes just about every program I write!) I need to scratch my brain when=
 I create try blocks.
>
> For example, I'm writing a little program do copy specific files to a USB=
 stick. To do the actual copy I'm using:
>
>     try:
>        shutil.copy(s, os.path.join(usbpath, songname))
>      except ...
>
> now, I need to figure out just what exceptions to handle. Let's see:
>
>   IOError  that means that the disk is full or otherwise buggered. Better=
 dump out of the loop.
>
> But, I know there can be other errors as well. Doing some tests, I know t=
hat certain filenames are invalid (I think a "?" or unicode char is invalid=
 when writing to a FAT32 filesystem). And, so what exception is that? Witho=
ut actually creating the error, I can't figure it out.

OSError.  In Python 3, I expect it would more specifically be a
FileNotFoundError, which is a subclass of OSError.

> In this case, I can run the program an number of times and parse out the =
errors and write code to catch various things. But, I think I'm missing som=
ething completely. Guess what I'm looking for is a list of possible (probab=
le?) errors for the shutil.copy() command. And, in a much bigger manual, fo=
r most other commands.

OSError will cover a wide swath of possible exceptions here.