> Man page of Python says
>
> -u Force stdin, stdout and stderr to be totally unbuffered. On
> systems where it matters, also put stdin, stdout and stderr in
> binary mode.
I don't know which version it is, but current 3.3 says:
“Force the binary I/O layers of stdin, stdout and stderr to be
unbuffered. The text I/O layer will still be line-buffered.”
> test_httpservers depends on this behavior, but was implemented as
> documented in Python 3.
I would argue that test_httpservers is wrong, since it uses print() in a
CGI script where sys.stdout.buffer.write() should really be used.