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From: John Baldwin <jhb@freebsd.org>
To: Yuri <yuri@rawbw.com>
Date: Mon, 2 Apr 2012 13:12:36 -0400
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	(bigwig.baldwin.cx); Mon, 02 Apr 2012 13:13:11 -0400 (EDT)
Cc: freebsd-hackers@freebsd.org, hackers@freebsd.org
Subject: Re: Is there any modern alternative to pstack?
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On Monday, April 02, 2012 12:39:26 pm Yuri wrote:
> On 04/02/2012 05:31, John Baldwin wrote:
> > Hmm, I don't know if the port has it, but I did some work on pstack a while
> > ago to make it work with libthread_db so it at least handles i386 ok.  It
> > needs to be modified to use something like libunwind though or some other
> > unwinder.  And possibly it should use libelf instead of its own ELF-parsing
> > code.
> 
> I see pstack -1.2_1 failing even on i386:
> 
> pstack: cannot read context for thread 0x1879f
> pstack: failed to read more threads

Yes, threads don't work for modern binaries (newer than 4.x) without my changes
to make it use libthread_db.  You can find the patch I used for this at
http://www.freebsd.org/~jhb/patches/pstack_threads.patch

-- 
John Baldwin