$PYTHONSTARTUP with python 2.7 and python 3.2

Question

I finally started using python 3 alongside python 2.7 on Linux.

I setup my python shell using a startup-script defined by $PYTHONSTARTUP. Due to incompatibilities I am unable to use the same script for both versions.

What is the easiest way to get one script for python 2.7, and another for python 3.2?

score 14 · Accepted Answer · edited Mar 12 '15 at 02:20

14

If you use Python 2 for some projects and Python 3 for others, then change the environment variable when you change projects.

Or, have your startup script look like this:

import sys
if sys.version_info[0] == 2:
    import startup2
else:
    import startup3

and split your real startup code into startup2.py and startup3.py

edited Mar 12 '15 at 02:20

nandhp

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answered Sep 08 '11 at 11:05

Ned Batchelder

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I went for the startup-script option, and wrote something similar to your code. I picked this answer because it was the first to suggest this solution. – mirk Sep 08 '11 at 12:11
1

`AttributeError: 'module' object has no attribute 'versioninfo'`. It's supposed to be `version_info`. – 2rs2ts Jul 12 '13 at 16:01

unutbu · Answer 2 · 2011-09-08T11:26:37.767

7

Set your $PYTHONSTARTUP to point to a script like this, which checks the version of Python being used, and then delegates to another startup script:

import sys
if sys.version_info[0]==2:
    from startup2k import *
elif sys.version_info[0]==3:
    from startup3k import *
else:
    # logging.warn('Unsupported version of Python')
    pass

edited Sep 08 '11 at 11:26

answered Sep 08 '11 at 11:07

unutbu

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score 2 · Answer 3 · answered Sep 08 '11 at 11:13

2

Define an alias for one of the python versions. In the alias, reset PYTHONSTARTUP as appropriate for that python version:

alias py3='PYTHONSTARTUP=/path/to/startup.py /other/path/to/python3.2'

answered Sep 08 '11 at 11:13

Michael J. Barber

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$PYTHONSTARTUP with python 2.7 and python 3.2

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