How to use export with Python on Linux

export, linux, python

Solution

`export` is a command that you give directly to the shell (e.g. `bash`), to tell it to add or modify one of its environment variables. You can't change your shell's environment from a child process (such as Python), it's just not possible.

Here's what's happening when you try `os.system('export MY_DATA="my_export"')`...

/bin/bash process, command `python yourscript.py` forks python subprocess
 |_
   /usr/bin/python process, command `os.system()` forks /bin/sh subprocess
    |_
      /bin/sh process, command `export ...` changes its local environment

When the bottom-most `/bin/sh` subprocess finishes running your `export ...` command, then it's discarded, along with the environment that you have just changed.

Problem

I need to make an export like this in Python : ``` # export MY_DATA="my_export" ``` I've tried to do : ``` # -*- python-mode -*- # -*- coding: utf-8 -*- import os os.system('export MY_DATA="my_export"') ``` But when I list export, "MY_DATA" not appear : ``` # export ``` How I can do an export with Python without saving "my_export" into a file ?

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