Calling the source command from subprocess.popen to update the os.environ.

[Hongyi Zhao]

Hi all,

Based on the methods here:

http://stackoverflow.com/questions/7040592/calling-the-source-command-
from-subprocess-popen/18897007#comment30954741_12708396

I use the following code the update the os.environ:

import os
from subprocess import check_output

# POSIX: name shall not contain '=', value doesn't contain '\0'
output = check_output("source /home/werner/env-intel-toolchains.sh;
         env -0", shell=True, executable="/bin/bash")

# replace env
os.environ.clear()
os.environ.update(line.partition('=')[::2] for line in output.split('\0'))

In the above code, the file /home/werner/env-intel-toolchains.sh will be 
sourced and its settings should be combined into the current os.environ 
of python.

But, I find that the above code will fail on the `os.environ.clear()' 
command as follows:

In[24]: import os
from subprocess import check_output
# POSIX: name shall not contain '=', value doesn't contain '\0'
output = check_output("source /home/werner/env-intel-toolchains.sh; env 
-0",   shell=True,
                      executable="/bin/bash")
# replace env
os.environ.clear()
os.environ.update(line.partition('=')[::2] for line in output.split('\0'))

Traceback (most recent call last):
  File "/home/werner/anaconda2/lib/python2.7/site-packages/IPython/core/
interactiveshell.py", line 3066, in run_code
    exec(code_obj, self.user_global_ns, self.user_ns)
  File "<ipython-input-24-816c472b62f2>", line 10, in <module>
    os.environ.clear()
  File "/home/werner/anaconda2/lib/python2.7/os.py", line 501, in clear
    unsetenv(key)
OSError: [Errno 22] Invalid argument

If I don't use the `os.environ.clear()' code line, it will work smoothly.

Any hints?

Regards
-- 
.: Hongyi Zhao [ hongyi.zhao AT gmail.com ] Free as in Freedom :.