Interactive os.environ vs. os.environ in script

[Peter Otten]

boris.smirnov at gmail.com wrote:

> Hi there,
> 
> I have a problem with setting environment variable in my script that
> uses qt library. For this library I have to define a path to tell the
> script whre to find it.
> 
> I have a script called "shrink_bs_070226" that looks like this:
> **********************************
> import sys, re, glob, shutil
> import os
> 
> os.environ["LD_LIBRARY_PATH"]='/path/Linux/rh_linux'
> 
> from qt import *
> ***********************
> 
> When I run this script I get this error:
> 
> 
>> python shrink_bs_070226.py
> Traceback (most recent call last):
>   File "shrink_bs_070226.py", line 25, in ?
>     from qt import *
>   File "/path/Linux/python/rh_linux/lib/python2.2/site-packages/
> qt.py", line 46, in ?
>     import libsip
> ImportError: libadamsqt.so: cannot open shared object file: No such
> file or directory
> 
> What is important here that when I set this variable interactive in
> python session, there is no problem with import.
> 
>> python
> Python 2.2.3 (#1, Aug  8 2003, 08:44:02)
> [GCC 3.2.3 20030502 (Red Hat Linux 3.2.3-13)] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import os
> 
>>>> import shrink_bs_070226
> Traceback (most recent call last):
>   File "<stdin>", line 1, in ?
>   File "shrink_bs_070226.py", line 25, in ?
>     from qt import *
> ImportError: No module named qt
> 
>>>> os.environ["LD_LIBRARY_PATH"]='/path/Linux/rh_linux'
> 
>>>> import shrink_bs_070226
>>>>
> 
> Could anybody explain me the logic here? Am I missing something?

Until Python 2.4 a failed import could leave some debris which would make
you think a second import did succeed.

Try

>>> import os
>>> os.environ["LD_LIBRARY_PATH"]='/path/Linux/rh_linux'
>>> import shrink_bs_070226 # I expect that to fail

in a fresh interpreter to verify that what you see is an artifact of your
test method.

Peter