Re: how to debug an emacs hang?

[Miles Bader]

On Tue, May 18, 2004 at 04:38:08PM -0700, John Owens wrote:
> I'd like to figure out how/where it's hanging, but I don't know how I
> might do so. Suggestions?

Run emacs in gdb, preferably from the src directory where you compiled emacs:

   $ cd ~/emacs-build/src
   $ gdb ./emacs

[There's a special .gdbinit file in that directory that defines handy emacs
debugging commands.]

When it hangs, hit C-z or something to exit to the debugger (you can't use
C-c like usual when debugging emacs, because emacs' standard .gdbinit file
changes gdb's SIGINT handling to make C-g work properly on ttys).

Then look at a C backtrace ("backtrace") and lisp backtrace ("xbacktrace")
to see what's up.

For more fun, do the above from another emacs session using emacs' `M-x gdb'
command.

-Miles
-- 
Any man who is a triangle, has thee right, when in Cartesian Space, to
have angles, which when summed, come to know more, nor no less, than
nine score degrees, should he so wish.  [TEMPLE OV THEE LEMUR]