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classification
Title: popen3 on windows loses environment variables
Type: Stage:
Components: Library (Lib) Versions: Python 2.4
process
Status: closed Resolution: fixed
Dependencies: Superseder:
Assigned To: Nosy List: georg.brandl, juneaftn, ompeag
Priority: normal Keywords:

Created on 2005-01-13 14:33 by juneaftn, last changed 2022-04-11 14:56 by admin. This issue is now closed.

Messages (6)
msg23950 - (view) Author: June Kim (juneaftn) Date: 2005-01-13 14:33
see the following test code:

#test_popen3_1.py
import os
FILENAME='c:\temp\test_popen3_2.py'
os.environ['FOOBAR']='foobar'
print os.environ['FOOBAR']
fs=os.popen3("c:\python24\python -u %s"%
FILENAME,'b')
print fs[1].read()

#c:\temp\test_popen3_2.py
print "from test_popen3_2.py"
import os;print os.environ['FOOBAR']

Running test_popen3_1.py is expected to print out:
foobar
from test_popen3_2.py
foobar

But it doesn't print the last foobar. It correctly prints 
out when run on python 2.3.

If the FILENAME is set to a relative path, as when you 
are in the c:\temp directory and the FILENAME is set to 
test_popen3_2.py, the code works correct.

Tests run on windows XP, SP1.

This bug is related to the cgi bug #1100235.
msg23951 - (view) Author: June Kim (juneaftn) Date: 2005-01-13 14:36
Logged In: YES 
user_id=116941

Sorry. I got confused. When FILENAME is absolute, popen3 
loses the environment variables, whereas it is relative, 
popen3 works fine.
msg23952 - (view) Author: AGunn (ompeag) Date: 2005-01-26 21:21
Logged In: YES 
user_id=1155133

I've tried recreating this problem and have had no luck.  I've 
tried three versions of python:  2.3, 2.4, and the current 
build version (2.5 something?).  I've also tried both absolute 
and relative paths.  All tests print out the second 'foobar' just 
fine.  I, too, am running XP, SP1.  

Any chance there's something special about how you are 
running the executables?  Say from a cygwin environment or 
something?
msg23953 - (view) Author: June Kim (juneaftn) Date: 2005-01-27 07:00
Logged In: YES 
user_id=116941

Oh, stupid me. The full path filename included '\t'. It
should've been escaped. Then the example code works with 2.3
and 2.4.

The real problem seems to be with os.environ.

I have reassured this problem exists on some XP SP1 boxes.

The test code is...

#test_popen3_1.py
import os
FILENAME='test_popen3_2.py'
env={};env['ENVIRON_UPDATE']='123';os.environ.update(env)
os.environ['ENVIRON_DIRECT_SETTING']='123'
cmdline='c:\python24\python.exe -u %s'%FILENAME
fs=os.popen3(cmdline,'b')
print fs[1].read()

#test_popen3_2.py
import os
if os.environ.has_key('ENVIRON_UPDATE'):print 'os.env.update
worked'
else:print 'os.env.update failed'
if os.environ.has_key('ENVIRON_DIRECT_SETTING'):print
'os.env assignment worked'
else:print 'os.env assignment failed'

Put these two files in the same path and run
test_popen3_1.py with python2.4 and python2.3.

Following is the result I got:

C:\test>\python23\python test_popen3_1.py
os.env.update worked
os.env assignment worked


C:\test>\python24\python test_popen3_1.py
os.env.update failed
os.env assignment worked

As you see the environment varaible that's updated with
os.environ.update has failed to get passed to popen3ed process.

This is the reason CGIHTTPServer.py fails to deliver
QUERY_STRING and etc. -- they are updated with
os.environ.update(env).
msg23954 - (view) Author: June Kim (juneaftn) Date: 2005-01-27 07:16
Logged In: YES 
user_id=116941

Now I got it. The reason is os.py in python2.4 has changed
so that the _Environ(UserDict.IterableUserDict) has lost its
update method -- there was on in python2.3.

To rectify the problem you just copy and paste the update
method from python2.3 os.py.

--- os.py       Thu Jan 27 07:09:38 2005
+++ os_new.py   Thu Jan 27 07:10:44 2005
@@ -435,6 +435,9 @@
                 return key.upper() in self.data
             def get(self, key, failobj=None):
                 return self.data.get(key.upper(), failobj)
+            def update(self, dict):
+                for k, v in dict.items():
+                    self[k] = v
             def copy(self):
                 return dict(self)

@@ -446,6 +449,9 @@
             def __setitem__(self, key, item):
                 putenv(key, item)
                 self.data[key] = item
+            def update(self, dict):
+                for k, v in dict.items():
+                    self[k] = v
             try:
                 unsetenv
             except NameError:
msg23955 - (view) Author: Georg Brandl (georg.brandl) * (Python committer) Date: 2006-07-30 11:40
Logged In: YES 
user_id=849994

This was fixed in rev. 38397.
History
Date User Action Args
2022-04-11 14:56:09adminsetgithub: 41436
2005-01-13 14:33:05juneaftncreate