os.environ['http_proxy'] not working
Question: > **Possible Duplicate:**  
>  [Is it possible to change the Environment of a parent process in
> python?](http://stackoverflow.com/questions/263005/is-it-possible-to-change-
> the-environment-of-a-parent-process-in-python)

I am using python 2.4.3. I tried to set my http_proxy variable. Please see the
below example and please let me know what is wrong. the variable is set
according to python, however when i get out of the interactive mode. The
http_proxy variable is still not set. I have tried it in a script and also
tried it with other variables but i get the same result. No variable is
actually set up in the OS.

    
    
    Python 2.4.3 (#1, May  1 2012, 13:52:57)
    Type "help", "copyright", "credits" or "license" for more information.
    >>> import os
    >>> os.environ['http_proxy']="abcd"
    >>> os.system("echo $http_proxy")
    abcd
    0
    >>> print os.environ['http_proxy']
    abcd
    >>>
    user@host~$ echo $http_proxy
    
    user@host~$
    


Answer: When you run this code, you set the environment variables, its working scope
is only within the process. After you exit (exit the interactive mode of
python), these environment will be disappear.

As your code "os.system("echo $http_proxy")" indicates, if you want to use
these environment variables, you need run external program within the process.
These variables will be transfer into the child processes and can be used by
them.

