Hello,

-V and --version both write to stderr not stdout.

On Thu, 3 Jan 2019, 1:29 pm Eric V. Smith <report@bugs.python.org wrote:

>
> Eric V. Smith <eric@trueblade.com> added the comment:
>
> -v writes to stderr, so this is the expected behavior. Although maybe this
> could be better documented.
>
> See issue 18338, where this was briefly discussed and a change was
> rejected.
>
> Maybe you're looking for -V (uppercase) or --version, which do write to
> stdout, at least in 3.x. I'm not sure where they write in 2.7, but it's
> much too late to change 2.7's behavior.
>
> I'm going to close this. If you find some of our documentation that says
> -v writes to stdout, then we can reopen this.
>
> This is not a Windows specific error, so I'm modifying the nosy list.
>
> ----------
> components: +Interpreter Core -Windows, ctypes
> nosy: +eric.smith -paul.moore, steve.dower, tim.golden, zach.ware
> resolution:  -> not a bug
> stage:  -> resolved
> status: open -> closed
> title: Subprocess.Popen('python -v',stdout=PIPE,stderr=PIPE,Shell=True)
> gives output in stderr -> python -v writes to stderr
>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <https://bugs.python.org/issue35646>
> _______________________________________
>