classification
Title: test_popen fails on Windows if installed to "Program Files"
Type: behavior Stage: needs patch
Components: Library (Lib), Windows Versions: Python 3.2, Python 3.1, Python 2.7
process
Status: open Resolution:
Dependencies: Superseder:
Assigned To: tim.golden Nosy List: BreamoreBoy, JosephArmbruster, eryksun, ezio.melotti, flox, georg.brandl, loewis, pjenvey, squeegee, tim.golden
Priority: normal Keywords: buildbot, needs review, patch

Created on 2006-09-15 12:59 by loewis, last changed 2014-06-08 06:36 by eryksun.

Files
File name Uploaded Description Edit
popen.diff loewis, 2006-09-15 12:59
issue1559298_trunk.diff brian.curtin, 2010-01-14 22:09 patch and docs against r77505
issue1559298_py3k.diff brian.curtin, 2010-01-14 22:12 py3k version of the patch
Messages (12)
msg51121 - (view) Author: Martin v. Löwis (loewis) * (Python committer) Date: 2006-09-15 12:59
test_popen fails in 2.5c2. The reason is that popen invokes

cmd.exe /c "c:\program files\python25\python.exe" -c
"import sys;print sys.argv"

cmd.exe does not support that syntax, and gives an
error (which silently disappears); the pipe read then
returns an empty string.

This problem exists atleast since Python 2.3.

To fix this, cmd.exe needs to be invoked as

cmd.exe /c "c:\program files\python25\python.exe" -c
"import sys;print sys.argv"

The attached patch fixes this by always wrapping the
command line with an addition pair of quotes.

It's not clear to me whether this can go into 2.5.1: an
application may already work around this problem by
passing extra quotes to popen, which would then break
if popen adds even more quotes.
msg51122 - (view) Author: Georg Brandl (georg.brandl) * (Python committer) Date: 2007-03-13 09:39
I don't see a difference between your two command lines here... did you mean to add additional quotes in the second example?
msg51123 - (view) Author: Martin v. Löwis (loewis) * (Python committer) Date: 2007-03-14 19:50
Indeed, this should read

cmd.exe /c ""c:\program files\python25\python.exe" -c "import sys;print sys.argv""
msg57615 - (view) Author: Joseph Armbruster (JosephArmbruster) Date: 2007-11-18 13:54
I applied the change to:

Python 2.6a0 (trunk:58651M, Nov 18 2007, 08:46:54) [MSC v.1400 32 bit
(Intel)] on win32

and test_popen passes appeared to pass.
msg88328 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2009-05-26 02:25
subprocess also needs this fix applied

Does the w9xopen command line below not need this?
msg90104 - (view) Author: Russ Gibson (squeegee) Date: 2009-07-04 04:14
What is needed is separate quoting for the command and the argument. 
Right now, test_popen only surrounds the entire command line with quotes:

"c:\Program Files\Python2.6\Python.exe -u c:\Documents and Settings\Russ
Gibson\cgi-bin\cgi.py"

It needs to the above as thus:

"c:\Program Files\Python2.6\Python.exe" -u "c:\Documents and
Settings\Russ Gibson\cgi-bin\cgi.py"

From the command line, the second case works, but the first doesn't. 
Neither work from os.popen in 2.6.2.

To make sure that popen works in all cases under windows, test_popen*
need to test with separate quotes around the command and argument.  That
will show the real problem with the current os.popen* implementation(s).

(yeah, I know, shut up and provide a patch...)
msg97790 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2010-01-14 22:09
This has come up recently and Martin's approach seems to work. I updated his patch for trunk, and test_popen passes when I run it with and without a space in the path. 

Russ Gibson's suggestion was already applied to test_popen, so the only code change is to posixmodule.c.
msg97791 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2010-01-14 22:12
Here is a py3k version of the previous patch. os.popen is implemented using subprocess.Popen, so the quoting change was made there.
msg97802 - (view) Author: Florent Xicluna (flox) * (Python committer) Date: 2010-01-15 08:52
It is on Python 2.7a2

>>> os.popen('"C:\\Python27\\python.exe" -c "import sys; print sys.argv" 42').read()
''

>>> os.popen('""C:\\Python27\\python.exe" -c "import sys; print sys.argv" 42"').read()
"['-c', '42']\n"

>>> os.popen3('"C:\\Python27\\python.exe" -c "import sys; print sys.argv" 42')[2].read()
'\'C:\\Python27\\python.exe" -c "import\' est pas reconnu en tant que commande interne ou externe, un programme executable ou un fichier de commandes.\n'

It may be related to the test_popen failure.
Actually, it seems that the outer double quotes are removed before executing the cmdstring:
  C:\Python27\python.exe" -c "import
 ^                                  ^
msg98512 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2010-01-29 14:25
Florent is correct. The patch seems to fix regular popen, but popen3 sees problems. I'll see if I can fit this in and have a look.

Also of note is that the other flavors of popen are not tested...at least not in Lib/test/test_popen.py or Lib/test/test_os.py
msg219999 - (view) Author: Mark Lawrence (BreamoreBoy) * Date: 2014-06-07 23:35
Is this worth pursuing given the wording here https://docs.python.org/3/library/subprocess.html#replacing-os-popen-os-popen2-os-popen3 ?
msg220020 - (view) Author: eryksun (eryksun) Date: 2014-06-08 06:36
This is fixed for subprocess.Popen in 2.7, 3.1, and 3.2; see issue 2304. In 2.7, nt.popen still has this problem. As mentioned above, it can be worked around by using subprocess.Popen as described here:

https://docs.python.org/2/library/subprocess.html#replacing-os-popen-os-popen2-os-popen3
History
Date User Action Args
2014-06-08 06:36:45eryksunsetnosy: + eryksun
messages: + msg220020
2014-06-08 00:17:37brian.curtinsetnosy: - brian.curtin
2014-06-07 23:35:44BreamoreBoysetnosy: + BreamoreBoy
messages: + msg219999
2010-08-25 07:39:39tim.goldensetassignee: tim.golden

nosy: + tim.golden
2010-08-24 20:33:43BreamoreBoysetversions: - Python 2.6
2010-01-29 14:25:07brian.curtinsetmessages: + msg98512
2010-01-29 13:11:01ezio.melottisetstage: patch review -> needs patch
2010-01-26 17:34:28ezio.melottisetnosy: + ezio.melotti
2010-01-15 16:26:30floxsetkeywords: + buildbot
2010-01-15 08:52:20floxsetnosy: + flox
messages: + msg97802
2010-01-14 22:12:04brian.curtinsetfiles: + issue1559298_py3k.diff

messages: + msg97791
2010-01-14 22:09:35brian.curtinsetfiles: + issue1559298_trunk.diff

components: + Library (Lib), - Tests
versions: + Python 3.1, Python 2.7, Python 3.2, - Python 3.0
keywords: + needs review
nosy: + brian.curtin

messages: + msg97790
2009-07-04 04:14:47squeegeesetnosy: + squeegee
messages: + msg90104
2009-05-26 02:25:11pjenveysetnosy: + pjenvey
messages: + msg88328
2009-03-30 03:08:38ajaksu2setstage: patch review
type: behavior
components: + Tests
versions: + Python 2.6, Python 3.0
2007-11-18 13:54:58JosephArmbrustersetnosy: + JosephArmbruster
messages: + msg57615
2006-09-15 12:59:09loewiscreate