Windows is not passing command line arguments to Python programs executed from the shell.

Question

I'm having trouble getting command line arguments passed to Python programs if I try to execute them directly as executable commands from a Windows command shell. For example, if I have this program (test.py):

import sys
print "Args: %r" % sys.argv[1:]

And execute:

>test foo
Args: []

as compared to:

>python test.py foo
Args: ['foo']

My configuration has:

PATH=...;C:\python25;...
PATHEXT=...;.PY;....

>assoc .py
.py=Python.File

>ftype | grep Python
Python.CompiledFile="C:\Python25\python.exe" "%1" %*
Python.File="C:\Python25\python.exe" "%1" %*
Python.NoConFile="C:\Python25\pythonw.exe" "%1" %*

Answer 1

Interesting. Works here using python 2.6 and Windows XP (5.1.2600):

C:\Documents and Settings\hbrown>python test.py foo
['test.py', 'foo']

C:\Documents and Settings\hbrown>test.py foo
['C:\\Documents and Settings\\hbrown\\test.py', 'foo']

C:\Documents and Settings\hbrown>test foo
['C:\\Documents and Settings\\hbrown\\test.py', 'foo']

C:\Documents and Settings\hbrown>type test.py
import sys
print sys.argv 

C:\Documents and Settings\hbrown>echo %PATHEXT%
.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.PY 

C:\Documents and Settings\hbrown>assoc .py
.py=Python.File

Answer 2

I think I solved this. For some reason there is a SECOND place in the registry (besides that shown by the file associations stored in HKEY_CLASSES_ROOT\Python.File\shell\open\command):

[HKEY_CLASSES_ROOT\Applications\python.exe\shell\open\command]
@="\"C:\\Python25\\python.exe\" \"%1\" %*"

This seems to be the controlling setting on my system. The registry setting above adds the "%*" to pass all arguments to python.exe (it was missing in my registry for some reason).

Answer 3

My setting was under yet another registry key, HKEY_CLASSES_ROOT\py_auto_file. The other keys mentioned also existed but Windows was using this one for some reason.