[comp.unix.questions] multiscreen unix

ted@braggvax.arpa (06/24/87)

There was a multi window terminal program for ttys called grotwin posted
a year or so ago.  I have used it a time or two, and it is rather nice, if
your baudrate is high enough.  Each window emulates a "grotty" tty and vi
etc will work.  BSD (ptys) only, I'm afraid.


				Ted Nolan
				ted@braggvax.arpa

barnett@vdsvax.steinmetz.UUCP (Bruce G Barnett) (06/25/87)

Re: Multiple-windows

Another program that provides multiple windows on a terminal is
screen. Posted March 87 in net.sources (52100001.tub.UUCP, 52100002.tub.UUCP)

Also: apparently wm needs a modified curses library. Apparently
several bugs have to be fixed. Which versions of -lcurses have the bugs,
and which versions have the fixes?

I have had difficulty with people using wm on a port selector, that
occassionally disconnects. The wm process will then (occassionally)
run wild, eating up CPU cycles, until someone kills it.

Has anyone else seen this?

(Version: Ultrix 1.2)
-- 
Bruce G. Barnett  (barnett@ge-crd.ARPA) (barnett@steinmetz.UUCP)
-- 
"The difference between a Buddha and an ordinary man is that one knows
the difference and the other does not."

trt@rti.UUCP (Thomas Truscott) (06/27/87)

> Also: apparently wm needs a modified curses library. Apparently
> several bugs have to be fixed. Which versions of -lcurses have the bugs,
> and which versions have the fixes?

I suspect that all standard versions of libcurses
are too buggy for wm to work properly when linked with them.
The wm distribution (mod.sources ~August 1985)
included source patches for the 4.2 libcurses.
I also sent the patches to UCB, hoping they would be incorporated in 4.3.
Alas they were not, leaving me three choices:
	Give up on curses, use 'termlib' directly.
	Figure out how to patch 4.3 libcurses.
	Link wm with the patched 4.2 libcurses.
This last method is easiest and is what we still do here.
After Matt Lennon and I found our 13th bug in libcurses
we should have gotten the message and stopped using it.
I think the libcurses hassle is why wm never caught on.
Personally I think wm is just wonderful and cannot live without it.
I am not familiar with the other wm-like programs out there
but suspect they too are wonderful (and I bet they skipped libcurses).
By the way, Rob Jacob first wrote wm for UNIX V6
and did not use libcurses either!

> I have had difficulty with people using wm on a port selector, that
> occassionally disconnects. The wm process will then (occassionally)
> run wild, eating up CPU cycles, until someone kills it.

If the line drops but wm does not get a SIGHUP the 'select' call
will fail forever.  (4.3 BSD 'vi' has a similar problem.)
That was fixed (about two years ago ...)
by counting consecutive select failures.
Every now and then I think about posting a revised version of wm
but then I remember the #$%* libcurses problem.
	Tom Truscott