public inbox for cygwin@cygwin.com
 help / color / mirror / Atom feed
From: Russell VT <russellvt@gmail.com>
To: Marco Atzeri <marco.atzeri@gmail.com>
Cc: cygwin@cygwin.com
Subject: Re: python3.9 failing?
Date: Thu, 23 Dec 2021 01:28:48 -0700	[thread overview]
Message-ID: <CANV2+nW3r877DAvgGuwy1HHWk0q4f-XDpKcvOq5k2g3s=yU8sQ@mail.gmail.com> (raw)
In-Reply-To: <2839cd60-8219-4b9a-b967-9519a36d247e@gmail.com>

On Thu, Dec 23, 2021 at 12:52 AM Marco Atzeri <marco.atzeri@gmail.com>
wrote:

> On 23.12.2021 06:50, Russell VT wrote:
> > On Tue, Dec 21, 2021 at 6:34 AM Achim Gratz <Stromeko@nexgo.de> wrote:
> >
> >> Marco Atzeri writes:
> >>> Without Python 3.9  installed python3 should link by default to the
> >>> next in the line (likely 3.8)
> >>
> >> While python3 still defaults to python38 alternatives should probably
> >> prioritize 38 over 39?
> >
> >
> > That's how I "fixed" mercurial on my own installation, as it was
> > complaining about missing the "parsers" module, from inside the Python
> 3.9
> > libraries, IIRC.
>
> Thanks for the report.
> It is caused by:
>
> $ head /usr/bin/hg -n 20
> #!/usr/bin/python3
>                   ^^ default 3.9
> ....
>
> libdir = '../lib/python3.8/site-packages'
>                         ^^ but really need 3.8
>

Thanks... python3 defaults to whatever you have "alternatives" set to...
looks like python's libdir doesn't quite obey those alternatives, though?


> No surprise is not working.
>
> A simple workaround is:
>

Simpler (and more-complete) workaround is:

% /usr/sbin/alternatives.exe --set python3 /usr/bin/python3.8
% /usr/sbin/alternatives.exe --set python /usr/bin/python3.8
% /usr/sbin/alternatives.exe --display python3
python3 - status is manual.
 link currently points to /usr/bin/python3.8
/usr/bin/python3.8 - priority 38
/usr/bin/python3.6 - priority 36
/usr/bin/python3.7 - priority 37
/usr/bin/python3.9 - priority 39
Current `best' version is /usr/bin/python3.9.


Read: that way, when you can't figure out why the "next python upgrade"
isn't working, you only need to go to the very first stop you should be
looking (ie /etc/alternatives), and not some random link that may or may
not always be the first one in your path.

Cheers -
RVT

-- 
Russell M. Van Tassell <russellvt@gmail.com>

  reply	other threads:[~2021-12-23  8:29 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-21 13:12 Henry S. Thompson
2021-12-21 13:26 ` Marco Atzeri
2021-12-21 13:33   ` Achim Gratz
2021-12-23  5:50     ` Russell VT
2021-12-23  7:52       ` Marco Atzeri
2021-12-23  8:28         ` Russell VT [this message]
2021-12-23  8:50           ` Marco Atzeri
2021-12-23 20:00       ` Henry S. Thompson
2021-12-21 13:36 ` Marco Atzeri
2021-12-21 18:10   ` Henry S. Thompson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CANV2+nW3r877DAvgGuwy1HHWk0q4f-XDpKcvOq5k2g3s=yU8sQ@mail.gmail.com' \
    --to=russellvt@gmail.com \
    --cc=cygwin@cygwin.com \
    --cc=marco.atzeri@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).