gdbserver tcsetpgrp() ??

gdbserver tcsetpgrp() ??

[Vijay Saha, Noida]

Hi

I have ported the gdbserver 5.3 on arm-linux target.
But as soon as debugging finishes, the target system gets logged out.

Then I had found that the "tcsetpgrp" in server.c:start_inferior() of
gdbserver was the culprit.
After commenting the line "tcsetpgrp (fileno (stderr), signal_pid);" , the
logout problem got solved !!!

I have also found that gdb-5.2 was not using this system call !!

What does this tcsetpgrp  actually doing ..?? (It has something to do with
foreground processing of terminal ..means..??)

How much is this necessary for remote debugging...??



**************************** clip of
server.c***************************************

start_inferior (char *argv[], char *statusptr)
{

  signal (SIGTTOU, SIG_DFL);
  signal (SIGTTIN, SIG_DFL);

  signal_pid = create_inferior (argv[0], argv);

  fprintf (stderr, "Process %s created; pid = %d\n", argv[0],
           signal_pid);
  signal (SIGTTOU, SIG_IGN);
  signal (SIGTTIN, SIG_IGN);

  /* chagall temp fix */
  /* when we use this function chagall gets logged out */
  //tcsetpgrp (fileno (stderr), signal_pid);

  /* Wait till we are at 1st instruction in program, return signal number.
*/
  return mywait (statusptr, 0);
}
**************************************end clip
*****************************************

Thanks and regards
Vijay

Re: gdbserver tcsetpgrp() ??

[Daniel Jacobowitz]

On Mon, Aug 04, 2003 at 06:35:17PM +0530, Vijay Saha, Noida wrote:
> Hi
> 
> I have ported the gdbserver 5.3 on arm-linux target.
> But as soon as debugging finishes, the target system gets logged out.
> 
> Then I had found that the "tcsetpgrp" in server.c:start_inferior() of
> gdbserver was the culprit.
> After commenting the line "tcsetpgrp (fileno (stderr), signal_pid);" , the
> logout problem got solved !!!
> 
> I have also found that gdb-5.2 was not using this system call !!
> 
> What does this tcsetpgrp  actually doing ..?? (It has something to do with
> foreground processing of terminal ..means..??)
> 
> How much is this necessary for remote debugging...??

Remote debugging will still work, sending control-c to interrupt the
program won't.  Console handling on your target is severely broken if
that call is causing a problem.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer