Re: Pinentry in emacs without X doesn't work reliably

[Tassilo Horn <tsdh@gnu.org>]

HASM <hasm@example.invalid> writes:

Hi HASM,

>> Now the problem is, that my keyboard input doesn't seem to get thru
>> to that pinentry dialog reliably.
>
> Did you install gnugp-1 on your system?

Nope, but that should work with GnuPG-2, too.

> Did you have or create this file
>   ~/.gnupg/gpg-agent.conf
> and have/add these lines into it:
>   allow-emacs-pinentry
>   pinentry-program /usr/bin/pinentry-emacs
> (replace the path above to where your pinentry-emacs is)?

Ah, cool.  That and installing the pinentry ELPA package made the thing
work!  Now my ~/.gnupg/gpg-agent.conf on the server is

--8<---------------cut here---------------start------------->8---
daemon
allow-emacs-pinentry
enable-ssh-support
max-cache-ttl 14400
max-cache-ttl-ssh 14400
default-cache-ttl 7200
default-cache-ttl-ssh 14400
pinentry-program /usr/bin/pinentry-emacs
--8<---------------cut here---------------end--------------->8---

> Did you add these lines to your emacs initialization:
>   (load "pinentry")
>   (pinentry-start)
>   (setq epg-gpg-program "gpg")
> (or use customize instead of the last line)?

Since I installed it via ELPA, I can just call (pinentry-start) without
loading before.  And `epg-gpg-program' is "gpg2" here.

But I wonder if

  pinentry-program /usr/bin/pinentry-emacs

is the right thing to do.  What if some other program needs a pinentry?
The pinentry ELPA package description doesn't say I need that line.

  https://elpa.gnu.org/packages/pinentry.html

However, when I remove that line, I get an error that there's no
pinentry program.

I hoped that allow-emacs-pinentry would somehow use pinentry-emacs if
running inside emacs and some other pinentry program for non-emacs
programs.

Daiki, since you've made the thing, do you have a clue what else I might
need?  I'm running gnupg-2.1.13 and pinentry-0.9.7, so according to the
pinentry ELPA package docs, those versions should be recent enough.  Or
maybe it's the other way round and pinentry-emacs spawns the right
pinentry depending on if we're running inside emacs?  Then that we need
to also set the pinentry-program to pinentry-emacs should be documented.

Bye,
Tassilo