Re: blank terminal on 7-th invocation of dialog

[Thomas Dickey]

On Fri, 22 May 2009, Max Arnold wrote:

> Hello all!
>
> I'm fighting almost whole day with strange problem. It happened while 
> developing simple gui with dialog utility inside X terminal (urxvt or 
> aterm). I've narrowed it to simple test window (text and dimensions are 
> not important):
>
> dialog --yesno "Sample text" 10 40
>
> I can launch this simple dialog six times in a row, and on 7-th it hangs 
> with blank terminal (but I'm able to abort it via Ctrl+C). No matter 
> what I'm doing then (launch in another terminal, issue 'reset' command), 
> it doesn't work anymore as well as any other console dialog windows 
> (other ncurses applications are not affected). The only way to recover 
> is to switch to console via Alt+Ctrl+F1, wait 2-3 seconds and then 
> switch back to X.

see below

> So far I've found four workarounds:
>
> 1. launch it inside xterm
>
> 2. launch it inside urxvt via command substitution:
>
> res=`dialog --stdout --yesno "Sample text" 10 40`
>
> 3. make urxvt report itself as xterm (urxvt.termName: xterm)

That's interesting (sounds like gpm or ncurses is trying to connect the
mouse differently in urxvt than in xterm).  ncurses uses the terminal
description to decide if it looks like xterm.

What does infocmp tell inside urxvt if you don't override $TERM ?

> 4. install ncurses-5.7 (this breaked many other binaries linked against 
> libncursesw.so.5 and since right now I don't plan to recompile 
> everything, I've switched back to 5.6)

It shouldn't break things (it's awkward to reinstall the libraries,
but applications that link against 5.6 should continue running against
5.7 - but keep the 5.6 libraries in case something is explicitly linked
against that version).

> Probably this problem started to happen after system upgrade which involved 
> many components,
> including xorg-1.5.  I've tested my earlier dialog scripts and they are also 
> affected.
>
> I'm on Gentoo, xorg-server-1.5.3-r5, ati-drivers-8.552-r2, ncurses-5.6-r2, 
> dialog-1.1.20080819,
> aterm-1.0.1-r1, rxvt-unicode-9.06, xterm-242

Sounds like one of the bugs in gpm.
I did a workaround for this last year, before releasing ncurses 5.7

--
Thomas E. Dickey
http://invisible-island.net
ftp://invisible-island.net