bug#15552: 24.3.50; epa-file-cache-passphrase-for-symmetric-encryption not respected with GnuPG 2.x

[Ted Zlatanov <tzz@lifelogs.com>]

On Wed, 09 Oct 2013 12:53:14 +0900 Daiki Ueno <ueno@gnu.org> wrote: 

DU> I didn't get the question correctly, then.

DU> Look at the matrix of (info "(epa) Caching Passphrases"), check when a
DU> user is suggested to "set up elisp passphrase cache".

DU> Anyway, the name is not so important to me, as long as it discourages
DU> the use of the variable, so it could be
DU> e.g. epg-file-yo-mama-wears-fancy-glasses-detection-enabled.

DU> https://news.ycombinator.com/item?id=6372466

Since it still works as described for GnuPG 1.x, please fix the
variable's docstring to mention that it doesn't work with 2.x.  You
could also add a reference to the manual page as shown above, and in the
manual you could synchronize the variable description with the
docstring, also adding the xref:

@defvar epa-file-cache-passphrase-for-symmetric-encryption
If non-@code{nil}, cache passphrase for symmetric encryption.  The
default value is @code{nil}.
@end defvar

Right now, you have to read the whole manual or search for the variable
name specifically to find that table.  It's not a big manual but it's
still nice to the user.

Thanks
Ted