[SOLVED] changing /usr/bin/python symlink

shelbydz · 2016-03-28 17:50:21

Hi,

I run awesome wm, vim, chrome and not much else. I develop in python for a living. But we use 2.7. It looks like the default /usr/bin/python is linked to python 3.5. Would I break any core Arch stuff by changing that to python 2.7? It would make my life a lot easier.

thx

Last edited by shelbydz (2016-03-30 11:28:01)

ewaller · 2016-03-28 18:10:59

Might I suggest virtualenv

ewaller@turing/home/ewaller % python
Python 3.5.1 (default, Mar  3 2016, 09:29:07)
[GCC 5.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>
ewaller@turing/home/ewaller % virtualenv2 venv
New python executable in /home/ewaller/venv/bin/python2
Also creating executable in /home/ewaller/venv/bin/python
Installing setuptools, pip, wheel...done.
ewaller@turing/home/ewaller % source venv/bin/activate
(venv) ewaller@turing/home/ewaller % python
Python 2.7.11 (default, Mar  3 2016, 11:00:04)
[GCC 5.3.0] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>
(venv) ewaller@turing/home/ewaller % pacman -Qo virtualenv2
/usr/bin/virtualenv2 is owned by python2-virtualenv 15.0.0-1
(venv) ewaller@turing/home/ewaller %

Edit: Sorry, I did not really answer your question. Changing your links to Python2 will break things. A lot of things.
The solution I proposed changes the PATH for the current process and future spawned sub-processes so that Python 2 is found first. Also, things installed using pip are local to that environment and don't impact the global space. In the mean time, other windows (processes) will still use the global version.

Last edited by ewaller (2016-03-28 18:42:55)

Scimmia · 2016-03-28 18:46:12

shelbydz wrote:

Hi,
I run awesome wm, vim, chrome and not much else. I develop in python for a living. But we use 2.7. It looks like the default /usr/bin/python is linked to python 3.5. Would I break any core Arch stuff by changing that to python 2.7? It would make my life a lot easier.
thx

So call /usr/bin/python2 like you should be doing anyway.
http://legacy.python.org/dev/peps/pep-0394/

WorMzy · 2016-03-28 18:47:33

I realise that this isn't what you asked, but you could "make your life a lot easier" by using appropriate shebangs instead of relying on /usr/bin/python being what you want: https://www.python.org/dev/peps/pep-0394/

ewaller · 2016-03-28 18:50:35

Of course, if one reads the posts my colleagues linked, it seems our distribution's policies were the genesis of that pep

shelbydz · 2016-03-30 11:27:50

Okay, thanks everyone. I did modify the shebang. That seems to be the easiest solution. These scripts are shared across multiple environments, including Ubuntu and OSX. The better alternative is probably a virtual environment.

thx

Trilby · 2016-03-30 11:35:12

shelbydz wrote:

The better alternative is probably a virtual environment.

"Better" based on what? The better alternative is to do it properly from the start which means using the right shebang. The links you've been provided with are not arch-specific guidelines, they are python coding guidelines.

Arch Linux

#1 2016-03-28 17:50:21

[SOLVED] changing /usr/bin/python symlink

#2 2016-03-28 18:10:59

Re: [SOLVED] changing /usr/bin/python symlink

#3 2016-03-28 18:46:12

Re: [SOLVED] changing /usr/bin/python symlink

#4 2016-03-28 18:47:33

Re: [SOLVED] changing /usr/bin/python symlink

#5 2016-03-28 18:50:35

Re: [SOLVED] changing /usr/bin/python symlink

#6 2016-03-30 11:27:50

Re: [SOLVED] changing /usr/bin/python symlink

#7 2016-03-30 11:35:12

Re: [SOLVED] changing /usr/bin/python symlink

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