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Date: Tue, 16 Jun 2009 06:53:00 -0000
Message-ID: <8ac60eac0906152353v7464a233ja58bf6d5280449e7@mail.gmail.com>
Subject: Re: how to r/w memory
From: Paul Pluzhnikov <ppluzhnikov@google.com>
To: loody <miloody@gmail.com>
Cc: gdb@sourceware.org
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On Mon, Jun 15, 2009 at 10:47 PM, loody<miloody@gmail.com> wrote:

> From the gdb document, we can use "x/nfu address" to read memory, but
> how we can write it?

I usually do:
  (gdb) set *(int *)0x80000000 = 0

If GDB knows has debug info associated with the memory location,
  (gdb) print var = 2
or
  (gdb) set var = 3
also work for me.

If GDB knows the symbol, but doesn't have debug info for it, you'll have
to do cast again:
  (gdb) set *(int *)&var = 4

Cheers,
-- 
Paul Pluzhnikov