Bug in python startup on linux? [Was: Wrong Executable? or something]

[Bernhard Herzog]

Siggy Brentrup <bsb at winnegan.de> writes:

> Clarence Gardner <clarence at beach.silcom.com> writes:
> 
> > This is a problem I've seen on many linux systems.  They're all RedHat or
> > Mandrake (extended RedHat).
> 
> Same holds for Debian slink aka 2.1
> 
> I did a little more testing and found out that results depend on your
> PATH setting.
> 
> Calling scripts with an empty PATH gives the expected results
[snip proof]
> I suspect a bug in the python startup routine, since sys.prefix
> and sys.exec_prefix are determined at configuration time.

Python tries to initialize sys.path based on the location of the python
executable. If argv[0] contains no '/' python searches $PATH for the
executable and starts from there.

On Linux it seems that a program called by the #! mechanism only gets
the basename of the file in argv[0], i.e. there's no '/' and therefore
python searches through the directories in $PATH, so it might get the
wrong one.

I'm not sure whether this is to be considered a bug in Linux or Python,
but Python could perhaps work around this on a Linux system by using
/proc/self/exe (which is a symbolic link to the executable of the
process) as reference when it searches $PATH for the file.

-- 
Bernhard Herzog	  | Sketch, a drawing program for Unix
herzog at online.de  | http://sketch.sourceforge.net/