On 23/01/15 at 09:51pm, Chi Hsuan Yen wrote: > Dear Arch enthusiasts, > > The package extra/java-runtime-common provides a convenient script > archlinux-java to handle co-existing JDK/JRE versions. I can use it to > switch between different versions of java implementations to accomplish > numerous tasks from testing the compatibilities of my programs to running > third party applications targeting on different platforms. Now I hope > there's also a simple script for the same thing but for python. On the > system, most of the scripts are written for python2 and some other scripts > are python3-specific. In most cases it's not a problem because I can fix > the scripts or use some tricks like $PATH to ensure the correct execution > of the programs. However, in large projects, doing either is time-consuming > and costly. Recently I'm building CyanogenMod on Arch Linux. It includes > lots of python scripts in the build system, and most of them requires > python2. Using the tip provided on the article about Python on ArchWiki > prevents lots of problems, but, however, some scripts have the shebang line > "#!/usr/bin/env python" or are invoked by some command like > "/usr/bin/python ...". I have to change the link /usr/bin/python to > pointing to python2 for further progress on building and changed it back > for my daily use. If there's an archlinux-python script, lots of time on > battling the difference between python2 and python3 does not exist anymore, > which I believe lots of users can benefit from it. Any ideas? > > Best Regards, > > Yen Chi Hsuan Hi, As I understand, you find a workaround thanks to Borja but I wander why nobody talked about Python VirtualEnv[1] (I thought it was created for such case). In your case (where you want to change python env just for building cyanogen then come back to python3), you can install "python-virtualenvwrapper" from repo then the first time you need to create the virtual env : $source /usr/bin/virtualenvwrapper.sh $mkvirtualenv -p `which python2` cyanogen $workon cyanogen and next time you just need to source the wrapper and change the env: $source /usr/bin/virtualenvwrapper.sh $workon cyanogen You can find more accurate details in [1] on the ArchWiki. Best regard, Fabien [1] https://wiki.archlinux.org/index.php/Python_VirtualEnv
