[comp.mail.elm] Memory fault -- screen problem

steve@raspail.UUCP (Steve Schonberger) (10/28/88)

I ran into a rather obnoxious problem.  My terminal emulation at home is
a vt52, which has no highlighting.  Thus, when I enter elm, as soon as
it tries to write the highlight bar for the current message, I get an
error.  It is Memory Fault, Segmentation Violation, or some such thing,
which implies that a NULL pointer is being followed instead of treated
as an end (or some other pointer-replated problem).  Getting a memory
fault error, and inflicting that on an inexperienced user (or even a
fairly knowledgable Unix hacker like me), is rather harsh treatment.  I
think that the screen handling code needs a little work so that the lack
of a terminal capability just causes the capability to not be used, like
not highlighting the current message at all, in this case, rather than
blowing up in the user's face.

This is not an absolute priority item, since I can work around it by
setting elm to arrow mode in options, but the bug should at least be
noted so people don't try to highlight on a non-highlighting terminal.

My own work-around was to put "alias elm elm -a" into my login macro
on my terminal program at home, so I can still use highlight at work.

I first noted this problem with elm 1.7b (what most people on my site
are using), but it is still there in elm 2.1 (which we just installed).

There was at least one other bug in 1.7b that bugged me in the area of
screen handling, but it's fixed.  Nice work folks.

	Steve Schonberger
	steve@raspail.uucp	raspail!steve@shamash.cdc.com
	...!uunet!rosevax!shamash!rapail!steve

steve@raspail.UUCP (Steve Schonberger) (11/13/88)

In article <999@raspail.UUCP>, I write:
> I ran into a rather obnoxious problem.  My terminal emulation at home is
> a vt52, which has no highlighting.  Thus, when I enter elm, as soon as
> it tries to write the highlight bar for the current message, I get an
> error.  It is Memory Fault, Segmentation Violation, or some such thing,
  [etc.]
> 
> My own work-around was to put "alias elm elm -a" into my login macro
> on my terminal program at home, so I can still use highlight at work.

I posted this without adequate experimentation, and I find that the "-a"
(force arrow mode) option does not work in the 2.1 I have (X-Mailer:
Elm [version 2.1 PL0]).  It uses the setting in the options file, with
no regard for the "-a" option.

I have a couple of work-arounds that I am thinking about, but haven't
decided which to use yet.  One is to put a hacked vt52 entry in my
termcap file, with bogus "so" and "se" entries.  The other is to set
arrow mode on and leave it that way, which works fine, but makes elm
look so bland on my fancy terminal at work.

Since I am apparently the only one griping about this problem, maybe
I will write a hack myself for it, time permitting.  I don't want to
spend my time on it though if someone else is working on something
that will cure this problem already.

 	Steve Schonberger
 	steve@raspail.uucp	raspail!steve@shamash.cdc.com
 	...!uunet!rosevax!shamash!rapail!steve