Portable python on window using msys

Table of Content

The main issues for portable python

python hardcoded full path in installed binary tool like pip.exe, easy_install.exe, ipython.exe, it is in main header located the end of exe file
#!C:\"path"\python.exe
you will get in trouble when you change parent directory of python or move it to another different drive.
if there are multi python version installed on window, only first one python path working fine

Let me show you how to easily to make multi portable python on window.

1) install multi python

standard installation to local drive then move to portable drive

L:\oldhorse\portableapps\Python27
L:\oldhorse\portableapps\Python3

now you can uninstall them from local drive.

2) setup multi python env

under msys /usr/local/bin,

the key just to add python folder and Script folder to PATH

/usr/local/bin/mypy2

#!/bin/bash

OLD_PATH="$PATH"
PATH=/portable/Python27:/portable/Python27/Scripts:$PATH
PYPATH=/portable/Python27
alias mypip="$PYPATH/python $PYPATH/Scripts/pip.exe"
alias myipy="$PYPATH/python $PYPATH/Scripts/ipython.exe"
alias mynb="$PYPATH/python $PYPATH/Scripts/jupyter-notebook.exe"
alias myeasy="$PYPATH/python $PYPATH/Scripts/easy_install.exe"
export OLD_PATH  PATH
export PS1='(mypy27) \u> \w
$ '

/usr/local/bin/mypy3

#!/bin/bash

OLD_PATH="$PATH"
PATH=/portable/Python3:/portable/Python3/Scripts:$PATH
PYPATH=/portable/Python3
alias mypip="$PYPATH/python $PYPATH/Scripts/pip.exe"
alias myipy="$PYPATH/python $PYPATH/Scripts/ipython.exe"
alias mynb="$PYPATH/python $PYPATH/Scripts/jupyter-notebook.exe"
alias myeasy="$PYPATH/python $PYPATH/Scripts/easy_install.exe"
export OLD_PATH  PATH
export PS1='(mypy3) \u> \w
$ '

add alias to /etc/profile:

alias mypy2='source /usr/local/bin/mypy2'
alias mypy3='source /usr/local/bin/mypy3'

start new session with expected python version:

$ mypy2 
(mypy27) oldhorse> ~
$ which -a python
/portable/Python27/python.exe
/c/Python27/python.exe

$ mypy3
(mypy3) oldhorse> ~
$ which -a python
/portable/Python3/python.exe
/c/Python27/python.exe

3) portable python tool

option1 – scite or notepad++ to replace

#!C:\"path"\python.exe
to
#!python.exe

option2 – directly run without any change even the path inside pip.exe could be wrong
python /"path"/pip.exe list

option3 – add alias in /etc/profile
alias mypip=’python /"path"/pip.exe’

then run as

mypip list

I prefer option3 since it has less effort but working good.