Passing environment variable to "subprocess" causes failure

[rdmurray at bitdance.com]

Quoth MRAB <google at mrabarnett.plus.com>:
> davidgould at davidgould.com wrote:
>  > I'm attempting to run subprocess and passing in an environment
>  > variable. When I do this the child process fails with an error. When I
>  > don't pass an environement variable it runs fine.
>  >
>  > BTW Running this code under Windows XP with Python 2.6.1
>  >
>  > Code A:
>  >
>  > p = subprocess.Popen( ['python', '-V'], env={ 'PYTHONPATH': 'C:/
>  > Documents and Settings/David Gould/workspace/DgTools/Common/Trunk/
>  > Source' } )
>  > print p.communicate()[0]
>  > print p.returncode
>  >
>  > Output:
>  >
>  > None
>  > -1072365564
>  >
>  > Code B:
>  >
>  > p = subprocess.Popen( ['python', '-V'] )
>  > print p.communicate()[0]
>  > print p.returncode
>  >
>  > Output:
>  >
>  > Python 2.6.1
>  > 0
>  >
>  > Any idea why passing an environment variable causes it to fail?
>  > Thanks.
>  >
> Are you sure it's not the path within the dict you're passing that's wrong?

Or there's something missing from the environment that python needs,
causing a non-zero return code when it is missing.  (That seems odd,
though.)

You ought to print communiicate()[1] to see if there is an
accompanying error message that would shed light on the problem.

--RDM