launching GnuPG daemons from the system session manager [was: Re: Environment variables for UPDATESTARTUPTTY of gpg-agent]

[Neal H. Walfield]

On Wed, 13 Jul 2016 14:10:27 +0200,
Daniel Kahn Gillmor wrote:
> 
> On Tue 2016-07-12 10:53:20 +0200, Werner Koch wrote:
> > You mean 2.0?  Since 2.1 auto starting the agent is the default and I
> > don't see why some other software should take part in it.  GnUPG would
> > not anymore be self-contained.  Anyway.
> 
> The rationale for having systemd manage the daemon startup on systems
> that are supported by systemd is twofold:
> 
>  * systemd can start up a daemon at login time; if you use gpg-agent for
>    ssh before you ever use gpg, gpg-agent will not be automatically
>    launched for you by any GnuPG tool if you are only manually invoking
>    ssh.
> 
>  * systemd can also safely shut down the daemons when the user finally
>    logs out.  GnuPG has no explicit support for cleanup/destruction of
>    running daemons, since it doesn't know when the user is logging out.
> 
> on non-systemd operating systems, the same argument probably applies to
> whatever integrated session management they offer.

I find it strange that gpg-agent is managed as part of the user's
session when it is independent of the session.  Concretely, if I have
multiple sessions open, e.g., desktop & multiple ssh instances, then I
expect them all to share the same gpg-agent.  Also, I wonder if this
doesn't negatively impact the use of --extra-socket.

:) Neal