Re: Fix needed for communication with gpg-agent

[Richard Stallman]

    > Since this was the main problem which we were concerned with, the
    > problem is reduced to find a way to block Emacs from reading from the
    > tty while pinentry needs it.

It is not intrinsically necessary to block Emacs from reading.
It would be enough if the code in Emacs does not read from the tty
during that time.

However, enabling pinentry to read from the tty probably requires
setting the tty's process group to the one that pinentry is in.  That
will probably have the effect that Emacs can't read from the tty
during that time.  If so, that is ok.