Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!wuarchive!decwrl!pyramid!cbmvax!vu-vlsi!dsinc!syd
From: syd@DSI.COM (Syd Weinstein)
Newsgroups: comp.mail.elm
Subject: Re: Arrow key bug in elm 2.2 PL14.
Message-ID: <1989Nov28.152904.8745@DSI.COM>
Date: 28 Nov 89 15:29:04 GMT
References: <1271@kuling.UUCP>
Reply-To: syd@DSI.COM
Organization: Datacomp Systems, Inc.  Huntingdon Valley, PA
Lines: 25

irf@kuling.UUCP (Bo Thide') writes:

>The command parsing in elm.c seems to presuppose that arrow key commands
>always start with ESC (\033).  This is not true.  A vt220 in 8 bit mode
>uses as the CSI (Command Seqeunce Introducer) the octal \233 to mean
>the same thing as ESC[ in 7 bit mode.  A quick and dirty hack to fix
>this is to add, in the file elm.c, 
>        case '\233':
>before line 646
>        case ESCAPE: ...

>I hope someone in the development team will look at this bug more thoroughly
>than I am able to.  There may be other problems of a similar nature elsewhere
>in the code.
This one is not a bug, but a limitation.  Elm was never designed to
handle arbitary cursor keys, only VT100 and HP.  Our goal was to let
curses do it, but as I have said before, we were never able to get
test programs running curses to be portable enough.  Oh, they
compiled just fine, but acted different.  Even when using a very
limited subset of curses.  (Too many vendors curses was broken).
-- 
=====================================================================
Sydney S. Weinstein, CDP, CCP                   Elm Coordinator
Datacomp Systems, Inc.				Voice: (215) 947-9900
syd@DSI.COM or {bpa,vu-vlsi}!dsinc!syd	        FAX:   (215) 938-0235