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From: Archie Cobbs <archie@whistle.com>
Message-Id: <199605230209.TAA10682@bubba.whistle.com>
Subject: stack trace library?
To: freebsd-questions@freebsd.org
Date: Wed, 22 May 1996 19:09:56 -0700 (PDT)
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Does there exist a library with routines that a program (linked with -g)
can use for doing stack crawls?

For example, suppose you

    signal(SIGSEGV, CatchBug);

Then when CatchBug() is called, you want the program to display a
stack trace from the point at which the signal occurred, a la gdb's
"where" command. Then we could have self debugging programs! :-)

CatchBug() might look something like this:

    extern void StabsSignalTrace(FILE *fp, struct sigcontext *ctx);

    void
    CatchBug(int sig, struct sigcontext *ctx)
    {
      warnx("caught fatal signal %s", sys_signame[sig]);
      warnx("please email bug report to xxx@foo.com with this trace:");
      StabsSignalTrace(stderr, ctx);
      exit(1);
    }

If there's no such library, is this possible and/or do-able?

-Archie

___________________________________________________________________________
Archie L. Cobbs, archie@whistle.com  *  Whistle Communications Corporation