Re: [gentoo-user] python 2.x vs 3.x

Mark Knecht <markknecht@×××××.com> [12-02-19 16:52]:
> On Sat, Feb 18, 2012 at 11:24 PM,  <meino.cramer@×××.de> wrote:
> > Mark Knecht <markknecht@×××××.com> [12-02-19 03:13]:
> >> In a current thread started by Meino where he is having trouble
> >> emerging hydrogen he reported the following quoted data to Neil. I
> >> don't believe Neil has responded yet but Meino's data brought me back
> >> to a question I've meant to ask for a while so I'll take this
> >> opportunity.
> >>
> >> From Meino:
> >>
> >> <QUOTE>
> >> With
> >>
> >>    eselect python list
> >>
> >> I get
> >>
> >> Available Python interpreters:
> >>  [1]   python2.6
> >>  [2]   python2.7
> >>  [3]   python3.1
> >>  [4]   python3.2 *
> >> </QUOTE>
> >>
> >> which shows python3.2 as the system wide default.
> >>
> >>    It's been my understanding ever since we first emerged any
> >> python-3.x version that we were not supposed to set any version of
> >> python3 as the system wide default. On all of my systems I have
> >> something like this:
> >>
> >> c2stable ~ # eselect python list
> >> Available Python interpreters:
> >>   [1]   python2.7 *
> >>   [2]   python3.2
> >> c2stable ~ # eselect python list --python2
> >> Available Python 2 interpreters:
> >>   [1]   python2.7 *
> >> c2stable ~ # eselect python list --python3
> >> Available Python 3 interpreters:
> >>   [1]   python3.2 *
> >> c2stable ~ #
> >>
> >>    Now, like Paul Hartman I didn't have any trouble building and
> >> running Hydrogen as a Jack client. It works just fine for me. However
> >> no one else seemed to have picked up on Meino's configuration which
> >> makes me wonder if I missed the memo to make the 3.x version of the
> >> system wide default.
> >>
> >>    What is the current best practice in this area?
> >>
> >> Cheers,
> >> Mark
> >>
> >
> > Hi Mark,
> >
> > after a lot of revdep-rebuilds and unresolved (or over-resolved)
> > references hydrogen builds fine. TADA! ;)
> > That is very nice ! :))
> >
> > Thank you very much for all your help.
> >
> > Unfortunately the svn-build of blender builds, but
> > the executable only prints:
> >
> >    Fatal Python error: Py_Initialize: Unable to get the locale encoding
> >    LookupError: no codec search functions registered: can't find encoding
> >    [1]    20570 abort      blender -noaudio
> >
> > Does anyone has built a daily snapshot of the svn blender successfully
> > against the systemwide python 3.2. ?
> >
> > How can I get blender to work?
> >
> > Cheers
> > mcc
>
> Meino,
>    First, congrats on getting Hydrogen going. May your life be full of
> head banging drum riff all day & night long.
>
>    Now, can you verify that the system wide python setting was in fact
> what made it build on your system? I know you were doing lots and lots
> of things. Was switching this back to 2.7 the thing that allowed
> Hydrogen to build for you?
>
>    As for Blender I really don't know what to do as I've never run it.
> Are you building Blender from an overlay or standard portage? If it's
> standard portage, and if the ebuild maintainer hasn't specifically
> said that you have to use 3.x then should a bug report be filed?
>
>    That may make no sense on other information you posted. I really
> haven't paid any attention to that part. Sorry.
>
>    Glad Hydrogen is working for you.
>
> Cheers,
> Mark
>

Hi Mark,

:)  

currently the rest of my gentoo system is banging my head... ;))))

:)

I did it the hard way:
I threw away the installation of python-3.2 in /usr/local which I need
to compile blender. Effect: Blender does no longer build.

I removed all python installation from my system except of the one
emerge uses.

I did a revdep-rebuild -pv to see, what applications and libs depends
on what version of python.

I filtered out all package which looks like libs or things used by
other programs and tried to build them against python 3.2: Some failed

I reinstalled python all versions of python, which were needed from
the dependencies shown by revdep rebuild.

With eselect python I set it to python 2.7.

I rebuild hydrogen, which wasn't confused by linux3 setting from out
space (plan9, I think).

Blender now builds and runs. The trick was, that the system wide
python 3.2 (which blender needs) uses lib64 while the previously 
under /usr/local installed one uses lib as the directory where its
own python code is store.

I build blender by myself. The pure vanilla code, freshly taken from
the developpers svn repository. No patch, no tweak. The real thing :)
;)))

Unfortunately blender spit out messages, that it is built against
libpng-1.2.27 ... and the whole systems only contains libpng-1.5*.

Currently I have no clue, what the reasons fro this is. Unfortunately
the CUDE renderer fails to do its job. I can start blender...but not
really much more.

This was a day in deep hack mode. Strace was my friend...as so often.

Will see how I can fix the rest of the problems.

The main problem of builing hydrogen was the python under /usr/local
I think...

Will see what hick up next ....

Cheers,
Meino