bug#25155: 25.1.90; Gnus: Sending a GnuPG-signed message executes the signing operation twice when using gcc field in the message (annoyance with smartcards)

[Teemu Likonen <tlikonen@iki.fi>]

In Gnus, when sending a GnuPG-signed message the signing operation is
executed twice if the message has gcc field for storing local copy. It
seems that the background "gpg --detach-sign" process is executed once
for the outgoing message and once for the local copy (gcc).

It's a small annoyance (and first a surprise) when using external
OpenPGP smartcard for the secret-key operation. My Yubikey smartcard has
to be touched before secret key operation is allowed. Some other
smartcards require pin code on physical machine.

Would a single sign operation suffice in Gnus? After all, it's just two
copies of the same message?




In GNU Emacs 25.1.90.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.14.5)
 of 2016-12-08 built on mithlond
Repository revision: 08decbd04b8346323b80f0dea84a462fe1f46b3f
Windowing system distributor 'The X.Org Foundation', version 11.0.11604000
System Description:	Debian GNU/Linux 8.6 (jessie)

Configured using:
 'configure --prefix=/home/dtw/.local --with-x-toolkit=gtk3
 --with-xwidgets --with-wide-int'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND DBUS GCONF GSETTINGS NOTIFY
GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB TOOLKIT_SCROLL_BARS
GTK3 X11 XWIDGETS

Important settings:
  value of $LC_MESSAGES: C
  value of $LANG: fi_FI.UTF-8
  value of $XMODIFIERS: @im=none
  locale-coding-system: utf-8-unix

Major mode: Group

Minor modes in effect:
  diff-auto-refine-mode: t
  gnus-topic-mode: t
  gnus-undo-mode: t
  ido-everywhere: t
  global-undo-tree-mode: t
  show-paren-mode: t
  winner-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
~/.emacs.d/omat/elisp/loaddefs hides /home/dtw/.local/share/emacs/25.1.90/lisp/loaddefs

Features:
(shadow emacsbug vc-git diff-mode conf-mode timezone dired-aux sh-script
smie executable shr dom sendmail wcheck-mode nnir gnus-fun flow-fill
sort gnus-cite qp mm-archive mail-extr gnus-bcklg gnus-async gnus-ml
disp-table bs char-fold misearch multi-isearch org-element org-rmail
org-mhe org-irc org-info org-gnus org-docview doc-view subr-x jka-compr
image-mode org-bibtex bibtex org-bbdb org-w3m org org-macro org-footnote
org-pcomplete pcomplete org-list org-faces org-entities org-version
ob-emacs-lisp ob ob-tangle ob-ref ob-lob ob-table ob-exp org-src ob-keys
ob-comint ob-core ob-eval org-compat org-macs org-loaddefs find-func
suomalainen-kalenteri solar cal-dst holidays hol-loaddefs cal-menu
calendar cal-loaddefs tabify imenu man gnus-topic nndraft nnmh epa-file
epa network-stream nsm auth-source starttls nnmbox nnnil gnus-agent
gnus-srvr gnus-score score-mode nnvirtual gnus-msg gnus-art mm-uu
mml2015 mm-view mml-smime smime dig mailcap nntp gnus-cache
gnus-bogofilter gnus-sum gnus-group gnus-undo nnnotmuch nnml gnus-start
gnus-cloud nnimap nnmail mail-source tls gnutls utf7 netrc nnoo
parse-time gnus-spec gnus-int gnus-range message dired format-spec
rfc822 mml mml-sec password-cache epg mm-decode mm-bodies mm-encode
mail-parse rfc2231 rfc2047 rfc2045 ietf-drums mailabbrev gmm-utils
mailheader gnus-win gnus gnus-ems nnheader gnus-util mail-utils mm-util
help-fns mail-prsvr wid-edit ido undo-tree diff paren winner rx
slime-fancy slime-trace-dialog slime-fontifying-fu slime-package-fu
slime-references slime-compiler-notes-tree slime-scratch
slime-presentations advice bridge slime-mdot-fu slime-enclosing-context
slime-fuzzy slime-fancy-trace slime-fancy-inspector slime-c-p-c
slime-editing-commands slime-autodoc slime-repl elp slime-parse slime
derived gud apropos compile etags xref cl-seq project eieio eieio-core
arc-mode archive-mode noutline outline easy-mmode pp comint ansi-color
ring hyperspec cl-macs thingatpt browse-url cl slime-autoloads edmacro
kmacro finder-inf tex-site info package epg-config seq byte-opt gv
bytecomp byte-compile cl-extra help-mode easymenu cconv cl-loaddefs
pcase cl-lib server time-date mule-util tooltip eldoc electric uniquify
ediff-hook vc-hooks lisp-float-type mwheel x-win term/common-win x-dnd
tool-bar dnd fontset image regexp-opt fringe tabulated-list newcomment
elisp-mode lisp-mode prog-mode register page menu-bar rfn-eshadow timer
select scroll-bar mouse jit-lock font-lock syntax facemenu font-core
frame cl-generic cham georgian utf-8-lang misc-lang vietnamese tibetan
thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek romanian
slovak czech european ethiopic indian cyrillic chinese charscript
case-table epa-hook jka-cmpr-hook help simple abbrev minibuffer
cl-preloaded nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote dbusbind inotify
dynamic-setting system-font-setting font-render-setting xwidget-internal
move-toolbar gtk x-toolkit x multi-tty make-network-process emacs)

Memory information:
((conses 16 486780 47564)
 (symbols 48 49228 7)
 (miscs 40 1479 2071)
 (strings 32 118529 18925)
 (string-bytes 1 3461974)
 (vectors 16 50528)
 (vector-slots 8 1676572 174589)
 (floats 8 1089 851)
 (intervals 56 21472 360)
 (buffers 976 116)
 (heap 1024 81998 12287))