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Re: Neat debugging trick with "screen" when xgdb is not an option

From: Victor Duchovni (Victor.DuchovniMorganStanley.com)
Date: Wed Mar 02 2005 - 09:38:25 CST

On Wed, Mar 02, 2005 at 10:35:17AM -0500, Wietse Venema wrote:

> Victor Duchovni:
> >
> > I rarely use X11, my world runs inside a "screen" session that I can
> > detach and re-attach at will, and that can be reached via SSH gateways
> > that prohibit port forwarding.
> >
> > This means that debugging Postfix servers processes can be tricky. Here
> > is a simple "screen" based recipe:
> >
> > main.cf:
> > debugger_command =
> > PATH=/bin:/usr/bin:/sbin:/usr/sbin; export PATH;
> > HOME=/root; export HOME;
> > screen -e^tt -dmS $process_name gdb $daemon_directory/$process_name $process_id &
> > sleep 1
>
> Does this require that one logs in as root prior to starting screen?
> If not, how does screen know what terminal it should be using?
>

The server-side of screen always sets "TERM=screen". The client side of
screen (when one re-attaches with "-r") translates the logical "screen"
to the physical terminal of the user.

This is also needed for detach/re-attach since the physical terminal
type can and does change between home and office, ...

--
        Viktor.