GDB command to write to memory

The command x is used to examine memory but i don't find the
command to write
directly a value in memory. I've tried X but it is not
recognized.

Thanks
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Guillaume MENANT wrote:
> 
> The command x is used to examine memory but i don't
find the command to
> write directly a value in memory. I've tried X but it
is not recognized.
> 
> Thanks
> 
The only solution i've found is the "set var"
command but it's limited in
use. Is there a more flexible command ?
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Guillaume MENANT <guillaume.menantgeensys.com> writes:

> The only solution i've found is the "set var"
command but it's limited in
> use. Is there a more flexible command ?

(gdb) set 0xdeadbeef = 42

Andreas.

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On Wed, 2008-02-27 at 22:38 -0800, Guillaume MENANT wrote:
> The command x is used to examine memory but i don't
find the command to write
> directly a value in memory. I've tried X but it is not
recognized.

There's no such command.  The general method is to use
an assignment expression.  You use a cast to determine
the size of memory (byte, word...) you want to write.

(gdb) set *(char *) 0xabcd = -1

You can do tricky things by using or omitting
"signed", 
and usually write up to an 8-byte word by using "long
long".