[petsc-dev] Configure won't find python

[Satish Balay]

Sure - the initial premise of this thread [as I understood] was: /usr/bin/python is python2. On python3 only installs - there is no /usr/bin/python (for ex: jedbrown/mpich-ccache docker file) - so we need to fix this issue in configure.

I'm guessing that most installs will have  /usr/bin/python as python2 or python3 - so missing /usr/bin/python is a smaller problem. Its not clear to me why this is missing in jedbrown/mpich-ccache - and how many OSes or distro will default to this mode.

Satish

On Fri, 17 Apr 2020, Jacob Faibussowitsch wrote:

> On macOS /usr/bin/python still defaults to:
> 
> $/usr/bin/python
> 
> WARNING: Python 2.7 is not recommended. 
> This version is included in macOS for compatibility with legacy software. 
> Future versions of macOS will not include Python 2.7. 
> Instead, it is recommended that you transition to using 'python3' from within Terminal.
> 
> Python 2.7.16 (default, Feb 29 2020, 01:55:37) 
> [GCC 4.2.1 Compatible Apple LLVM 11.0.3 (clang-1103.0.29.20) (-macos10.15-objc- on darwin
> Type "help", "copyright", "credits" or "license" for more information.
> 
> /usr/bin/env python also points to the same python 2.7
> 
> Best regards,
> 
> Jacob Faibussowitsch
> (Jacob Fai - booss - oh - vitch)
> Cell: (312) 694-3391
> 
> > On Apr 17, 2020, at 11:31 PM, Jed Brown <jed at jedbrown.org> wrote:
> > 
> > Satish Balay via petsc-dev <petsc-dev at mcs.anl.gov> writes:
> > 
> >>>> Given that python2 has gone the way of the dodo perhaps petsc should be looking for python3 over python2.
> >> 
> >> I'm not sure what would be common across distros/OSes wrt /usr/bin/python - one shouldn't assume this is always python2 [and that it won't exist for python3 only installs]
> >> 
> >> I have:
> >> 
> >> balay at sb /home/balay
> >> $ /usr/bin/python --version
> >> Python 3.7.6
> > 
> > My distro's /usr/bin/python has been python3 since, I believe, 2011.
> > 
> > That said, an executable named python3 also exists at that path.
> 
>