[Web-SIG] Fwd: Can writing to stderr be evil for web apps?

[anatoly techtonik]

Hi,

Martin expressed concerns that using logging module with stderr output
can break web applications, such as PyPI. I couldn't find any proof or
denials for this fact, and it became a showstopper for me for further
contributions to PyPI, because clearly I can't write good code without
the sense of confidence.

Here is the commit in question:
https://bitbucket.org/techtonik/pypi-techtonik/changeset/5396f8c60d49

I was redirected here from python-dev. So can anybody tell where are
those stdout/stderr fears coming from and how to dispell them?
(include in WSGI notes)

Please, CC (this didn't work - I subscribed, so don't care).
--
anatoly t.