[Xastir] Ubuntu 10.04 problem with repository xastir package

[Tom Russo]

On Fri, May 07, 2010 at 06:41:59PM -0400, we recorded a bogon-computron collision of the <rtg at aapsc.com> flavor, containing:
> Just installed the latest ubuntustudio 10.04, and of course, did an 
> immediate 'apt-get install xastir'.  It gave me v1.9.4, compiled way back 
> in 2008!  I can't complain much, because I have to admit I'm running 1.9.5 
> on my other system, and haven't recompiled it myself since late 2008.
>    I'll go check out the wiki directions for compiling on 10.04, but I 
> thought I'd document here an anomaly I discovered in this version before I 
> blow it away:
>   1) It exhibits the characteristic Ubuntu 'disappearing buttons on 
> dialogs'.  No surprise there.

Turn off "Desktop effects."

>   2) If I right-click anywhere on the map, I do not get the expected 
> context menu.  Instead, xastir captures my mouse pointer, and from that 
> moment forward, I can't move the mouse pointer anywhere outside the map 
> window.  I can't even get to the top menu bar.  The keyboard shortcuts 
> 'alt-F' doesn't work either.
>    My escape turned out to be ctrl-alt-F2, which gets me out of X and gives 
> me a login prompt.  After logging in, I issue a `killall xastir`, then hit 
> alt-F7 to return to X, to find xastir gone, and I have control of my mouse 
> again.

This was fixed in CVS *today*.

The issue is in fact a bug in the X server that impacts *all* Motif programs,
not just Xastir.  Turns out that Motif uses something called a "passive grab"
in XmCreatePopupMenu and relies on something the X server has always done to
release the grab --- something that version 1.7.4-1.7.5 of Xorg-server has
stopped doing.  Version 1.7.6 (not yet released) has apparently fixed it again,
but in the meantime all Motif programs are busted in the same way.

The ideal fix is to update to a version of Xorg-server that has the fix.  
Another option is to manually patch Motif libraries.  The third is to figure 
out a way to work around it in applications.

The maintainers of the Grace plotting package on Debian came up with a 
work-around that I worked into Xastir this morning --- when one of my systems 
got its X server upgraded to 1.7.5 and started exhibiting the behavior.  Given 
a system on which I could actually test, I was able to get it fixed in a few 
minutes.

If you update Xastir to CVS and rebuild, you should have a functional version
with less trouble than you would have had yesterday.

-- 
Tom Russo    KM5VY   SAR502   DM64ux          http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236        http://kevan.org/brain.cgi?DDTNM
 "It is better to live on your feet than to die with your knees."
  -- Mil Millington on running, in Instructions for Living Someone Else's Life