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From: Russ Cox <rsc@swtch.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] validateaddress
Date: Wed, 12 Aug 2009 07:59:31 -0700	[thread overview]
Message-ID: <dd6fe68a0908120759x71e8dfcet668e2d084f6f4a58@mail.gmail.com> (raw)
In-Reply-To: <1B2326AB-19A1-4C73-9BA6-0033FA0191F8@ar.aichi-u.ac.jp>

so strcmp is being called a lot but klook isn't.
that means that klook is looping inside, which
basically means the p->next pointer is pointing
at itself.

final script:

kw
mem(kw, "30X")  // dumps hash table
*(kw+25*4)
mem(*(kw+25*4), "16X")  // dumps entry for 'in'
*(**(kw+25*4)\s)  // should print 'in'

i expect that the value printed for *(kw+25*4)
in the third line will also be the third value printed
by the mem on the fourth line, meaning that
the hash table entry in question has a next
pointer pointing at itself.  assuming that is true,
i think we're close to the end of what can be done.
the hash table list isn't supposed to loop back
on itself but it is.  that means some kind of dangling
pointer or other memory corruption error, which
we're not likely to find retroactively.

russ


  reply	other threads:[~2009-08-12 14:59 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-08-10  6:11 Kenji Arisawa
2009-08-10 17:13 ` erik quanstrom
2009-08-11  3:57   ` Kenji Arisawa
2009-08-11  4:07     ` erik quanstrom
2009-08-11  5:26       ` Kenji Arisawa
2009-08-11 15:27         ` Russ Cox
2009-08-12  6:48           ` Kenji Arisawa
2009-08-12 14:59             ` Russ Cox [this message]
2009-08-13  1:39               ` Kenji Arisawa
2009-08-13  2:15                 ` Russ Cox

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