Path: utzoo!utgpu!watmath!uunet!mcvax!kth!draken!tut!korppi!mh
From: mh@korppi.tut.fi (Harjula Mikko)
Newsgroups: gnu.emacs.vms
Subject: Re: emacs on the VAX???
Message-ID: 
Date: 23 Jul 89 23:42:48 GMT
References:  
Sender: News@tut.fi
Reply-To: mh@korppi.UUCP (Harjula Mikko)
Organization: Tampere University of Technology, Finland
Lines: 76

In article  wsincc@eutrc3.urc.tue.nl (Wim van Dorst) writes:
>In article  JONES@ohstpy.mps.ohio-state.edu (Bob Jones [VAX-Man] Home: (614)447-0214) writes:
>>will emacs running under VMS [v 4.7] on a VAX 8650 understand non-ANSI type 
>>terminals?  If it uses SMG$ routines, it probably will.
>>If anyone can help me on this, I would be very interested in perhaps getting
>>a [free?] copy of the emacs source code.

...

>Although this is mailed to gnu.emacs may I point you to the
>existence of MicroEmacs, a small version for many OS'ses

I used to use GNU Emacs in VMS 4.7 for some time because of its
superior capabilities (I think it was version 18.47) .  It works well
with almost any terminal, and it was the only way I could use my own
exotic terminal at home. Another main reason for using emacs in VMS
was that I had to use UNIX and VMS side by side and changing from
editor to another was a PAIN.

I have to point out some problems though. Getting the editor to work
on a non-DEC terminal is not the whole picture even if it is the most
vital part.  First you cannot use any VMS commands that rely on a
certain terminal type and there are more of them that you would want
to believe. I couldn't even get the command line editing to work
properly even though my exotic terminal is pretty close to VT52 (but
not close enough). Not having all the commands you are used to becomes
a real pain in a while.

The second problem is that emacs is not designed to such an exotic
system as VMS and has some problems when used there. I didn't look
what country you are from, but in most european countries the native
language includes characters outside of the 27-character US set. This
causes a problem because DEC has decided to place those characters in
the range 128-255 (that is in VT200 national mode) and Emacs cannot
handle these 8-bit characters properly. It displays \XXX for each
character where XXX is an octal number and that messes up your line
lengths etc. But what's even worse you cannot insert those characters.
What I did was that I set my terminal to seven bit VT100 mode and used
those {, | and } characters I am used to. Then I used a program to
convert these to DEC 8-bit equivalents when printing. This was a bit
cumbersome.

One problem is that starting emacs in VMS is painfully slow. This is
avoided by using a special command file KEPT_EDITOR.COM which is
included in emacs distribution. The first time you run it, it spawns
your emacs and if you leave it using CTRL-Z (which detaches from the
process) the next time you run KEPT_EDITOR.COM it attaches to the old
emacs process. This is faster than starting any DEC editor and has the
advantage of getting you to the same place where you left last time.

One really annoying problem is that emacs uses CTRL-S and CTRL-Q for
editing commands. You can disable these but there stil remains a
problem with slow VT100 compatible terminals (for example, I think
VT132 uses software to interpret various control sequences as opposed
to VT100 that has it all in hardware). So VT100 termcap entry is much
too fast for VT132 and the screen doesn't update correctly (sometimes
you have to reset the terminal to get it working again). I assume the
same applies to all slow VT100 emulators. Of course you could add your
own terminal definition with some added padding. I tried it, but I
didn't have termcap documentation and fiddling with termcap didn't
produce results soon enough so I decided to stick with real VT100's.

And of course you would have to move those useful commands (CTRL-S and
CTRL-Q) to some other key sequency (possibly disabling some other
useful commands) and end up having different command definitions on
VMS and UNIX. And one of the reasons for going to emacs was to have
the same editing commands in both machines...

In spite of all these problems I used emacs in all my work in VMS
because I feel it has superior capabilities. Now those problems are
over for me because I no longer have to work with VMS. At least not at
the moment, but I stil have that emacs in TK50 somewhere :-)

Mikko Harjula     UUCP: ...mcvax!tut!mh	INTERNET: mh@tut.fi
Home: Lukonmaenkatu 5 H 40 33700 Tre, Finland; phone +358 31 181177
Work: SQ Consulting OY Kanslerink. 8 33720 Tre, Finland; phone +358 31 165205