[Zope] system calls

[Arenz, Ralph]

Hi,

i' am using external methods in zope and in this external methods (python
module(s))
i try to do a system call via the module os.
A  little more concrete:

	1) assume that the the python module is foo.

	2) In Zope i have defined the external method call_pdflatex
	    in the module foo	

	3)The system command in foo is: 
		os.system( 'pdflatex -interactions= '"nonstopmode"'
[path]')

	4)The Folders which resides on the filesystem (linux)have  the right
group and user
	   adjustments according to that of Zope.

	5)Starting python the interactive way(as root or as ather user) and
testing the system-call 
	   will return the right result. 

	6)Also positiv is to call a system command which causes no
fileoperation like 'ping' or 'echo'
	   form Zope via external method 

As you can see in point 5 it is no problem by python e.g no permissions to
write to a file or a folder.
In fact it is a Zope problem (I suppose !).
Is there a way to grant a permission to Zope (External Method Product) to
allow system calls ??
Can anybody help me ?

I'am running out of ideas.

Ralph