bug#15553: 24.3.50; epg.el and GnuPG 2.x cause unavoidable pinentry prompts for symmetrically encrypted files

[Teodor Zlatanov]

1. Install GnuPG 2.x, don't run gpg-agent
2. Open file.gpg, X or curses pinentry dialog pops up

The suggested workaround is to run gpg-agent.

Problems:

- on a headless server this can lock up Emacs

- if the GPG agent is dead, locked up, or not running, there's no remedy

- the X pinentry dialog is very non-specific ("Enter passphrase") so
  there's no way to know what passphrase is being requested and why if
  you don't have the specific instance in focus.

- there's no way to avoid the prompt in favor of an Emacs minibuffer query



In GNU Emacs 24.3.50.2 (x86_64-unknown-linux-gnu, GTK+ Version 3.4.4)
 of 2013-09-20 on flea.lifelogs.com
Bzr revision: 114415 rgm@gnu.org-20130921005207-1eq49miu7feptu8i
Windowing system distributor `The X.Org Foundation', version 11.0.11304000
System Description:     Gentoo Base System release 2.2