Re: debugging emacs

[Adam Sulmicki]

: I am not sure what the reason for this is, but I suspect
: it has to do with the code in mouse-show-mark.  You could
: study what happens there.

cool, thanks, this hint got me back on track!

following code around I found that the place here emacs hang
is in src/keyboard.c:1800:read_char()

there are lines like (not quoted all of them for 
brewity:
--------------------------------------------------
wrong_kboard:                                   2198

#ifdef MULTI_KBOARDX                            2216
      if (! NILP (c) && (kb != current_kboard))
        {
          if (single_kboard)
            goto wrong_kboard;                  2228
        }
#endif                                          2235
--------------------------------------------------

the issue is that when it is on the "other" frame/display
it thinks it is got wrong keyboard and loops in the
wrong_kboard: -> goto wrong_kboard loop.

if I simply in the above example diable this particular
#ifdef, emacs appears to work fine,and does not hang anymore.
at least not for this particular bug.

this bring me to question. what are this "muti-keyboard"
stuff anyway? brief grep over emacs sources did not seem
to turn info what it is supposed to do.

and past that it is the quest to find "The Right"(tm) solution
for this particular bug, but that's for tomorrow.