python - specifically handle file exists exception

python exception ioerror
cogitoergosum picture cogitoergosum · Dec 26, 2013 · Viewed 33.3k times · Source

I have come across examples in this forum where a specific error around files and directories is handled by testing the errno value in OSError (or IOError these days ?). For example, some discussion here - Python's "open()" throws different errors for "file not found" - how to handle both exceptions?. But, I think, that is not the right way. After all, a FileExistsError exists specifically to avoid having to worry about errno.

The following attempt didn't work as I get an error for the token FileExistsError.

try:
    os.mkdir(folderPath)
except FileExistsError:
    print 'Directory not created.'

How do you check for this and similar other errors specifically ?

Answer

falsetru picture falsetru · Dec 26, 2013

According to the code print ..., it seems like you're using Python 2.x. FileExistsError was added in Python 3.3; You can't use FileExistsError.

Use errno.EEXIST:

import os
import errno

try:
    os.mkdir(folderPath)
except OSError as e:
    if e.errno == errno.EEXIST:
        print('Directory not created.')
    else:
        raise

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