Re: Fix needed for communication with gpg-agent

[Richard Stallman <rms@gnu.org>]

    One possible way might be to have emacs start its own gpg-agent daemon,
    specifying a custom pinentry program that uses emacs itself for
    interaction (Emacs would set the GPG_AGENT_INFO environment variable to
    communicate that to invocations of gpg).  That seems a wee-bit
    heavyweight, since Emacs generally doesn't know whether you're going to
    run gpg, but I suppose it might be a reasonable option for people that
    use a long-running Emacs session.

Emacs could start this demon only the first time you try to use gpg.
Then it would not be wasteful.

We need to solve this problem one way or another now, because we
decided to fix a certain security hole by telling users to use
gpg-agent.  We don't need the most elegant possible fix, but we
need something reasonable to use.