Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!mcsun!ukc!tcdcs!swift.cs.tcd.ie!ccvax.ucd.ie!clissman
From: clissman@ccvax.ucd.ie
Newsgroups: comp.protocols.iso.dev-environ
Subject: The innards of the FTAM implementation
Summary: call for information on the level 6 to7 interface in the FTAM imp.
Keywords: ftam modification, functions, data structures
Message-ID: <47905.27b2d259@ccvax.ucd.ie>
Date: 8 Feb 91 16:31:21 GMT
Organization: University College Dublin
Lines: 25

I am trying to modify the FTAM implementation included in ISODE 6.0, but
am having difficulty tying down the data structures involved. 
Can anyonne tell me
1: which procedures are used by the ftam functions to gain access to the 
presentation layer, ie how do FDataRequest, FReadWriteRequest and so on get
their data from level 6 ? It seems they may use PDataRequest, can someone 
confirm this ? 
2: What kind of a data strcture is used to move user file contents from
level 7 to level 6 and vice versa. And where are these data structures
defined. (It seems a PE structure may be used, but I'm having problems
finding a definition for PE in the .h files.)

I want to get at this data and encrypt it before it arrives in level 6, and
then 
decrypt it as it goes from level 6 to level 7. Has anyone got clever ideas
on this one ? 
My gratitude for any help received,

Thanks

Ciaran

Ciaran Clissmann
Dept Comp Sci
Univ. Coll. Dublin Ireland