How to debug gdb using gdb ?

How to debug gdb using gdb ?

[Smith John]

hi,guys:

   I am  researching  gdb source code ,  and  I want  to  debug  it
using  its  executable file .
   but  how can I send  command  to  the  debugged  gdb procedure
which is children  process  ,

  as the gdb which is parent process will  deal with every command
inputed from  the command line ,so I get no way to communicate  with

  that debugged gdb procedure.



any advice?


thanks!

Re: How to debug gdb using gdb ?

[Tom Emerson]

http://sourceware.org/gdb/current/onlinedocs/gdbint/Debugging-GDB.html#Debugging-GDB

On Tue, Aug 7, 2012 at 10:18 AM, Smith John <baseboy126@gmail.com> wrote:
> hi,guys:
>
>    I am  researching  gdb source code ,  and  I want  to  debug  it
> using  its  executable file .
>    but  how can I send  command  to  the  debugged  gdb procedure
> which is children  process  ,
>
>   as the gdb which is parent process will  deal with every command
> inputed from  the command line ,so I get no way to communicate  with
>
>   that debugged gdb procedure.
>
>
>
> any advice?
>
>
> thanks!



-- 
Tom Emerson
tremerson@gmail.com
http://www.dreamersrealm.net/tree

Re: How to debug gdb using gdb ?

[Jan Kratochvil]

On Tue, 07 Aug 2012 16:18:01 +0200, Smith John wrote:
>    but  how can I send  command  to  the  debugged  gdb procedure
> which is children  process  ,

I find most easy to make child GDB non-interactive.  So that you do not have
to re-enter the exact commands to reproduce the problem each time.  Therefore
use -ex (or -x) for the child GDB:

gdb -ex 'b breakpoint.c:9152' -ex r --args ./gdb ~/t/try5 -ex 'b display' -ex r -ex up -ex b -ex 'info b' -ex 'p/x $pc' -ex 'info line *$pc' -ex 'set confirm no' -ex q -q


Regards,
Jan