Re: bad epg.el+GPG2 behavior: unavoidable passphrase pinentry prompt

[Ted Zlatanov <tzz@lifelogs.com>]

On Mon, 30 Sep 2013 18:49:11 -0400 Stefan Monnier <monnier@iro.umontreal.ca> wrote: 

>> Should I open a bug, then, with the suggested workaround?  Or wait?  The
>> multiple popups are really annoying.

SM> I must say I don't really understand what is the problem you're
SM> describing (I mean: in what way does it affect Emacs), so I'll let
SM> you judge.

SM> AFAIK it's perfectly OK to popup a password prompt when needed and
SM> I don't know under what circumstance this would be a problem.

Using symmetric (passphrase) encryption:

open authinfo.gpg in a buffer -> prompt
edit
save -> prompt
VCS commit -> 2 or 3 prompts

4-5 prompts, I lost counts.  This is the default behavior with GnuPG
2.0.20 and can't be turned off in a config file.  To fix it, epg.el must
be changed to use `--passphrase-fd=0 --batch' as I found today.

The old behavior was, when GPG_AGENT_INFO was disabled, to ask for the
password in an Emacs prompt.  That fix doesn't work now.

Daiki Ueno, however, told me the behavior was different in 2.1 with
--pinentry-mode=loopback but I can't find such a release even though I
found the commit.  So I have no idea what the right fix is, at this
point.

I hope that summary helps.

Ted