Skip site navigation (1)Skip section navigation (2)
Date:      09 Feb 2002 23:57:59 +0100
From:      Dag-Erling Smorgrav <des@ofug.org>
To:        Zhihui Zhang <zzhang@cs.binghamton.edu>
Cc:        freebsd-hackers@freebsd.org
Subject:   Re: Ptrace and SIGTRAP problem
Message-ID:  <xzppu3ez2iw.fsf@flood.ping.uio.no>
In-Reply-To: <Pine.SOL.4.21.0202091443001.1954-100000@opal>
References:  <Pine.SOL.4.21.0202091443001.1954-100000@opal>

next in thread | previous in thread | raw e-mail | index | archive | help
Zhihui Zhang <zzhang@cs.binghamton.edu> writes:
> - PT_CONTINUE + waitpid() works fine, the trace program prints out values.

This is expected behaviour.

> - PT_CONTINUE alone does not work but no core-dump caused by SIGTRAP
> - PT_DETACH + waitpid() does not work and core-dump
> - PT_DETACH alone does not work and core-dump.

These three cases are unexpected.  I'll have to dig some more into
this, but I'm afraid I won't have time until some time next week.

> Who is sending the SIGRAP (5) signal?

execve(2) in kern_exec.c posts SIGTRAP if the process has debugging
turned on (which it does as a result of PT_TRACE_ME). 

DES
-- 
Dag-Erling Smorgrav - des@ofug.org

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?xzppu3ez2iw.fsf>