gdb and emacs

[Shankar K E]

Hi,

I want to display line numbers when I am debugging using gdb under emacs
(using gud).

The source file is displayed in the other window, I need line numbers to
be displayed along with the source file. I want this to happen only when
I use gdb under emacs.

How do I start gud after the environment settings have been changed,
gud seems to be using the settings when emacs started off from the
shell.

I restart emacs whenever there is a change in the environment, could
you suggest me an alternative option.

Also Is there any environment variable which is set if I am within a
emacs session. I would like to do some additional processing in my
.bashrc when emacs is launched.

Please let me know on how to go about it.

Thanks in Advance
--

Shankar