Backtrace.

[barmar@THINK.COM]

   Date: Mon, 5 Jun 89  15:05:06 MDT
   From: snicoud@atc.boeing.com (Stephen Nicoud)

   How can a process get a backtrace of its own stack?

See the section in book 2A on the Condition system and the Debugger.
It describes a multitude of functions for getting pointers to stack
frames and accessing information in them.  It describes just about
everything you'd need to reimplement the debugger yourself.  Look up
DBG:WITH-ERRING-FRAME in the index, and this should get you close
(unfortunately, the page numbers in Symbolics indexes are only an
approximation to reality -- hopefully this will be improved in future
manuals written with Concordia).

You could also look at the source to the debugger.  I believe this is
in the Basic Source category.

						barmar