Re: Descriptor leak in python 2.4 subprocess module

[Tim Golden]

Michel Lespinasse wrote:

Hi,

I hit an issue with the following python code:

try:
get_orient = subprocess.Popen (['jpegexiforient', '-n', pathfull],
stdin = subprocess.PIPE,
stdout = subprocess.PIPE)
orient = get_orient.communicate ()[0]
except:
orient = None

The intent of this was to read the exif orientation of a picture, or just
use None if jpegexiforient can not run.

The application worked fine on my devel machine but I noticed that on a
different host, it crashed due to running out of file descriptors.
After investigation I found out that the above code was responsible,
leaking two file descriptors per invocation if jpegexiforient is not
installed on the host.

I don't see any way to fix it in my code either, since get_orient is not
defined in the exception path, there is no way I can close its file
descriptors myself. I believe this is a bug in the subprocess module,
it should make sure to clean up after itself when getting out on the
exception path.

This looks like a duplicate of http://bugs.python.org/issue3210.
Can you confirm if this seems likely (and, if so, perhaps add
a note to the bug indicating that the problem is on Linux as well)?

TJG