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From: gdiaz@9grid.es
To: 9fans@9fans.net
Subject: [9fans] naive acid debugging
Date: Wed, 15 Jul 2009 17:26:31 +0200	[thread overview]
Message-ID: <73875a2249f78ec9cd60d0ef39b5f9e6@9grid.es> (raw)

Hello

While understanding how refs work inside nupas, i decided to try to implement the same function nupas has to find mailbox references in acid langauge, so i did:

defn findmboxrefs(mb,fids) {
	local f, refs;
	f=fids;
	while f!=0 do {
		print("f=", f\X,"\n");
		if f->mb==mb then
			refs++;
		print("f->mb=", f->mb\X,"	=?	mb=",mb\X,"\n");
		f=f->next;
	}
	print("refs ==", refs,"\n");
}

using a Broken nupas (broked by an assert call), i got this:

acid: findmboxrefs(*checkmboxrefs:mb,fids);
f=0x0003a090
f->mb=0x00000000	=?	mb=0x0004a468
f=0x0004bf68
f->mb=0x8d1c2444	=?	mb=0x0004a468
f=0x89ffffe4
<stdin>:75: (error) indir: can't read address 0x89ffffe4: bad arg in system call

is that related to something wrongly done in the acid function?
that means that there is an f which is pointing to an incorrect place?
or means that as the process is broken, acid cannot read some parts of it?

i forgot another possible issue, the broken process is owned by another user, i just chmod'ed /proc/pid/*. . . .

thanks

gabi




             reply	other threads:[~2009-07-15 15:26 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-15 15:26 gdiaz [this message]
2009-07-15 16:41 ` erik quanstrom
2009-07-15 18:30   ` Russ Cox
2009-07-15 17:52     ` gdiaz
2009-07-15 15:37 gdiaz

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