raw memory write?

raw memory write?

[Németh Márton]

Hi!

I'm testing an embedded system with gdb using remote target.

Examining memor works fine as described at
http://sources.redhat.com/gdb/onlinedocs/gdb_9.html#SEC59

But I couldn't find any easy command with I could modify the content of
a given memory address, only if I create a one-byte-long file containing
my data.

For example:
--------------------------------------------------------
(gdb) x/b 0x800000C0
0x800000c0:     0x00
(gdb) restore one.dat binary 0x800000C0
Restore file one.dat offset 0x800000c0 start 0x0 end 0x0
Restoring binary file one.dat into memory (0x800000c0 to 0x800000c1)
(gdb) x/b 0x800000C0
0x800000c0:     0x01
(gdb) restore zero.dat binary 0x800000C0
Restore file zero.dat offset 0x800000c0 start 0x0 end 0x0
Restoring binary file zero.dat into memory (0x800000c0 to 0x800000c1)
(gdb) x/b 0x800000C0
0x800000c0:     0x00
(gdb)
--------------------------------------------------------

Do I need to create a file when I want to write a byte of data?

Thanks.

	Márton Németh

Student of Budapest University of Technology and Economics, Hungary

Re: raw memory write?

[Daniel Jacobowitz]

On Wed, Jan 21, 2004 at 08:08:35PM +0100, Németh Márton wrote:
> Hi!
> 
> I'm testing an embedded system with gdb using remote target.
> 
> Examining memor works fine as described at
> http://sources.redhat.com/gdb/onlinedocs/gdb_9.html#SEC59
> 
> But I couldn't find any easy command with I could modify the content of
> a given memory address, only if I create a one-byte-long file containing
> my data.
> 
> For example:
> --------------------------------------------------------
> (gdb) x/b 0x800000C0
> 0x800000c0:     0x00
> (gdb) restore one.dat binary 0x800000C0
> Restore file one.dat offset 0x800000c0 start 0x0 end 0x0
> Restoring binary file one.dat into memory (0x800000c0 to 0x800000c1)

Try:
(gdb) set *(char *)0x800000C0 = 0x01

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer