Python versions

[Princess Nell]

Is there any generic configuration that allows running a given python prog with a python version other than the system default? On my system, both python 2 and 3 are installed, 3 is the default, but there is some software in portage that doesn't seem like python3 and will probably never get fixed. Sure, editing the launcher to use python2 instead of python is possible, but will be overridden next time the port is re-emerged.

The software in question is games-arcade/solarwolf.

[TomWij]

Let's say you want a specific package CATEGORY/PKG to use 2.7; create a file /etc/portage/env/python2.7 and set PYTHON_TARGETS="python2_7" and PYTHON_SINGLE_TARGET="python2_7" in it, then add another file /etc/portage/package.env with as content CATEGORY/PKG python2.7 which will cause that package to use Python 2.7. This will cause the emerge to set the right shebang upon emerge. For more details on these configuration files, see `man portage`.

[dol-sen]

Forgive me Tom, but that seems like the hard way. You can set the python flags in package.use to override the PYTHON_TARGETS setting in make.conf

[TomWij]

Depends on whether you want to set it only once and be able to apply it to multiple packages or whether you want to keep changing it as new Python versions come and apply it to a single package, each approach has its (dis)advantages.