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Date: Tue, 24 Apr 2012 13:09:00 -0000
From: Luis Gustavo <luis_gustavo@mentor.com>
Reply-To: "Gustavo, Luis" <luis_gustavo@mentor.com>
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To: Xin Tong <xerox.time.tech@gmail.com>
CC: gdb@sourceware.org
Subject: Re: Hardware watchpoint for read
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Hi,

On 04/24/2012 10:02 AM, Xin Tong wrote:
> Hello
>
> I am wondering that can gdb insert hardware watch point for read to
> the watched memory ? can other debugger do that ? is it supported in
> hardware watchpoint ?
>
> Thanks
>
> Xin
>

Read watchpoints are hard to implement as soft-watchpoints, so they're 
usually implemented as hardware watchpoints.

If a debugger knows how to properly set the bits in the hardware, either 
through ptrace or other means, it can configure a read/write/read-write 
watchpoint. Depends on hardware support really.

Regards,
Luis