I am trying to invoke a C++ program from an external method. Platform is Linux. The C++ program returns HTML. Note that the Python function is working properly from the Python command line; That is, ExecCGI.xCGI("./websim") outputs all the expected html. I have placed the C++ program in the same folder as the ExecCGI module. The C++ program works from apache: here's an example of the program's output, which is what I'm trying to get into Zope: http://63.203.42.146/cgi-bin/websim ExecCGI module: import sys, os, string def xCGI( cmdLine ): """ Run an external command and return its standard output as a string. """ f = os.popen( cmdLine ) lines = f.readlines() status = f.close() if status: raise "CGI returned error: %d" % status[1] return string.join( lines ) External Method that calls the C++ program: Id ExecCGI Title Test Function name xCGI Python module file (without suffix) ExecCGI DTML Method that calls the External Method: <dtml-var standard_html_header> <h2><dtml-var title_or_id></h2> <dtml-let cmdLine="'./websim'"> <dtml-var "ExecCGI(cmdLine)"> </dtml-let> <dtml-var standard_html_footer> Traceback: Traceback (innermost last): File /usr/local/Zope/lib/python/ZPublisher/Publish.py, line 214, in publish_module File /usr/local/Zope/lib/python/ZPublisher/Publish.py, line 179, in publish File /usr/local/Zope/lib/python/Zope/__init__.py, line 202, in zpublisher_exception_hook (Object: ElementWithAttributes) File /usr/local/Zope/lib/python/ZPublisher/Publish.py, line 165, in publish File /usr/local/Zope/lib/python/ZPublisher/mapply.py, line 160, in mapply (Object: TestWS) File /usr/local/Zope/lib/python/ZPublisher/Publish.py, line 102, in call_object (Object: TestWS) File /usr/local/Zope/lib/python/OFS/DTMLMethod.py, line 150, in __call__ (Object: TestWS) File /usr/local/Zope/lib/python/DocumentTemplate/DT_String.py, line 502, in __call__ (Object: TestWS) File /usr/local/Zope/lib/python/DocumentTemplate/DT_Let.py, line 145, in render (Object: cmdLine="'./websim'") File /usr/local/Zope/lib/python/DocumentTemplate/DT_Util.py, line 335, in eval (Object: ExecCGI(cmdLine)) (Info: ExecCGI) File <string>, line 0, in ? File /usr/local/Zope/lib/python/Products/ExternalMethod/ExternalMethod.py, line 248, in __call__ (Object: ExecCGI) (Info: (('./websim',), {}, None)) File /usr/local/Zope/Extensions/ExecCGI.py, line 11, in xCGI TypeError: (see above) File Permissions in /usr/local/Zope/Extensions/: -rwxr-xr-x 1 ewalstad users 318 May 20 17:31 ExecCGI.py -rw-r--r-- 1 ewalstad users 576 May 20 17:03 ExecCGI.pyc -rwxr-xr-x 1 ewalstad users 336081 May 20 17:13 websim Any help is GREATLY appreciated! Thanks, Eric.