Path: utzoo!mnetor!uunet!mcvax!guido
From: guido@cwi.nl (Guido van Rossum)
Newsgroups: comp.windows.x
Subject: Re: Why XSendEvent sets hibit of type?
Message-ID: <165@piring.cwi.nl>
Date: 13 Jan 88 12:19:41 GMT
References: <8801090141.AA08906@arc.com> <22555@ucbvax.BERKELEY.EDU>
Reply-To: guido@cwi.nl (Guido van Rossum)
Organization: "Stamp Out BASIC" Committee, CWI, Amsterdam
Lines: 17

>The main Good Reason for XSendEvent to set the high bit is to forestall
>fraud...

Hmm, it would seem that there are enough other fraudulent things you can
do to a user once you've gotten access to the display she's using.
Setting the high bit on event types can only give a false feeling of
security.

A different form of security is that of program correctness: there are
cases where the server guarantees that particular events will or won't
be sent, or will be sent in a particular order.  Applications may rely
on this.  Events inserted at random points in the event stream by other
clients may spoil the assumptions.  However, even here (as everywhere
else) I'd prefer "trust, but check".
--
Guido van Rossum, Centre for Mathematics and Computer Science (CWI), Amsterdam
guido@cwi.nl or mcvax!guido or (from ARPAnet) guido%cwi.nl@uunet.uu.net