Date: Thu, 24 Sep 1998 15:26:14 +0200 (CEST)
Message-Id: <199809241326.PAA10226@login-2.eunet.no>
From: "Gisle Vanem" <giva AT bgnett DOT no>
To: djgpp AT delorie DOT com
Subject: preserving exception context
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I have a rather large program that must exit gracefully even after
crashing.  I've installed a signal-handler for SIGSEGV/SIGFPE which
is supposed to exit safely. In the exception handler I have:

  signal (SIGSEGV,SIG_DFL);  /* to prevent nested SIGSEGV's */
  shutdown();                /* lot of tidying up here */
  raise (SIGABRT);           /* traceback, exit */

The problem is that if shutdown() also crashes, I get a traceback for
that crash and not the originating fault. How can I (besides writing
shutdown() foulproof) get a traceback for both or a least only the first
crash.

The crash in shutdown() is most certainly a consequence of the first crash
so that it's not so (IMHO) important to trace. (i.e. overwritten data etc.)

Note, this is all with djgpp 2.02 alpha, where `raise(SIGABRT)' seems to
work as intended (I sometimes got stange results in 2.01).
Otherwise I use DOS 6.22, QEMM 7.53 and CWSDPMI on a 90MHz Pentium PC.

Gisle V.