##############################################################################
# $Id: FAQ.txt,v 1.1 2004/01/08 02:27:35 schilz Exp $
#
# Copyright (c) 2004  Dr. Thomas Schilz
#
# This file is part of MozPython.
#
# MozPython is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# MozPython is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with MozPython; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
##############################################################################

------------------------------------------------------------------------------
Q: Why can't we use the "file" protocol to read .py files?

A: In nsDocShell::DoURILoad POST data is only set up for http channels.
   So if we use "file" channels we have no way to access POST data.

------------------------------------------------------------------------------
Q: Is there no other way to access POST data?

A: No. POST data is extracted in nsFormSubmission::SubmitTo
   (file content/html/content/src/nsFormSubmission.cpp) and the passed on
   to nsWebShell::OnLinkClickSync to nsDocShell::InternalLoad
   to nsDocShell::DoURILoad, where it's finally discarded if the
   channel for the protocol does not implement nsIHttpChannel.

------------------------------------------------------------------------------
Q: Why don't we use use an internal nsFileChannel instance instead of
   copying most of it's methods?

A: nsFileChannel only accepts "file:..." URLs. If we change "cfh" to "file"
   for the nsFileChannel, then this scheme somehow leaks through. The result
   is that relative URLs are openend with the "file" protocol.

------------------------------------------------------------------------------
Q: What is the mpdlpxpc library needed for?

A: PyToHTMLConv uses a static method of one of PyXPCOM's classes
   (Py_nsISupports::PyObjectFromInterface) in the _xpcom library.
   Since the names of class methods get mangled by the compiler it is not
   possible to find them with their normal name in a library dynamically
   loaded at runtime. mpdlpxpc is linked against _xpcom and contains a
   "extern C" function PyObjectFromInterface which simply calls the static
   class method.

------------------------------------------------------------------------------
Q: Why not link PyToHTMLConv against _xpcom?

A: Then if PyXPCOM isn't installed on the system PyToHTMLCons will fail to load.