bug#54214: 28.0.91; rcirc failed to report disconnection

[Ken Raeburn]

I had a VPN connection go down, over which I had been running one of
three IRC sessions. The rcirc buffers for the channels on that server,
the server buffer, and the *Messages* buffer, gave no indication at all
that there was a problem. No disconnected status in the mode line, no
status messages logged, no reported attempts to reconnect. I only
noticed it when failing to ssh to another host.

Before reconnecting, I did check “M-x list-processes”, and the server
connection for the third IRC server was not present, indicating that
Emacs recognized the TCP connection was gone. After I brought the VPN
back up, “/reconnect” brought the connection back up.


In GNU Emacs 28.0.91 (build 1, x86_64-redhat-linux-gnu, X toolkit, cairo 
version 1.17.4, Xaw3d scroll bars)
 of 2022-01-11 built on 7efb8fbccc97436880211dbad44871a1
Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
System Description: Fedora Linux 35 (Workstation Edition)

Configured using:
 'configure --build=x86_64-redhat-linux-gnu
 --host=x86_64-redhat-linux-gnu --program-prefix=
 --disable-dependency-tracking --prefix=/usr --exec-prefix=/usr
 --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc
 --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib64
 --libexecdir=/usr/libexec --localstatedir=/var
 --sharedstatedir=/var/lib --mandir=/usr/share/man
 --infodir=/usr/share/info --with-dbus --with-gif --with-jpeg --with-png
 --with-rsvg --with-tiff --with-xft --with-xpm --with-x-toolkit=lucid
 --with-gpm=no --with-modules --with-harfbuzz --with-cairo --with-json
 --with-native-compilation build_alias=x86_64-redhat-linux-gnu
 host_alias=x86_64-redhat-linux-gnu CC=gcc 'CFLAGS=-DMAIL_USE_LOCKF -O2
 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches
 -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2
 -Wp,-D_GLIBCXX_ASSERTIONS
 -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong
 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic
 -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection'
 LDFLAGS=-Wl,-z,relro
 PKG_CONFIG_PATH=:/usr/lib64/pkgconfig:/usr/share/pkgconfig'

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 M17N_FLT MODULES NATIVE_COMP NOTIFY
INOTIFY PDUMPER PNG RSVG SECCOMP SOUND THREADS TIFF TOOLKIT_SCROLL_BARS
X11 XAW3D XDBE XIM XPM LUCID ZLIB

Important settings:
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Perl

Minor modes in effect:
  rcirc-track-minor-mode: t
  display-time-mode: t
  desktop-save-mode: t
  global-edit-server-edit-mode: t
  which-function-mode: t
  icomplete-mode: t
  shell-dirtrack-mode: t
  global-hi-lock-mode: t
  hi-lock-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tab-bar-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
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t

Load-path shadows:
/home/raeburn/elisp/with-editor hides 
/home/raeburn/.emacs.d/elpa/with-editor-20211028.2105/with-editor
/home/raeburn/.emacs.d/elpa/systemtap-mode-20151122.1940/systemtap-mode hides 
/usr/share/emacs/site-lisp/systemtap-mode
/home/raeburn/.emacs.d/elpa/p4-20150721.1937/p4 hides 
/usr/share/emacs/site-lisp/perforce/p4
/home/raeburn/.emacs.d/elpa/transient-20211101.2251/transient hides 
/usr/share/emacs/28.0.91/lisp/transient

Features:
(shadow emacsbug tramp-cmds cl-print ielm mailalias smtpmail sendmail
mail-extr cal-move sort url-cache url-http url-gw url-auth cperl-mode
with-editor grep vc-hg vc-bzr ispell cus-edit pp cus-start misearch
multi-isearch gnutls network-stream nsm add-log reveal perl-mode
face-remap dired-aux python tramp-sh yaml-mode mule-util dockerfile-mode
mhtml-mode css-mode color js sgml-mode facemenu ruby-mode sh-script smie
executable texinfo texinfo-loaddefs bug-reference rst compile
org-element avl-tree generator ol-eww eww xdg url-queue thingatpt mm-url
ol-rmail ol-mhe ol-irc ol-info ol-gnus nnselect gnus-search eieio-opt
speedbar ezimage dframe ol-docview doc-view image-mode exif ol-bibtex
ol-bbdb ol-w3m ol-doi org-link-doi vc-git diff-mode vc-dispatcher
cc-mode cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine
cc-vars cc-defs view jka-compr ob-shell comp comp-cstr warnings cl-extra
help-mode rcirc gnus-art mm-uu mml2015 mm-view mml-smime smime dig
gnus-sum shr kinsoku svg dom gnus-group gnus-undo gnus-start gnus-dbus
dbus xml gnus-cloud nnimap nnmail mail-source utf7 netrc nnoo gnus-spec
gnus-int gnus-range message rmc puny dired dired-loaddefs rfc822 mml
mml-sec epa derived epg rfc6068 epg-config mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader gnus-win gnus
nnheader gnus-util rmail rmail-loaddefs rfc2047 rfc2045 ietf-drums
text-property-search mail-utils mm-util mail-prsvr wid-edit time desktop
frameset cus-load kr-init docker-tramp tramp-cache vagrant-tramp dash
tramp tramp-loaddefs trampver tramp-integration files-x tramp-compat
parse-time ls-lisp org-protocol org ob ob-tangle ob-ref ob-lob ob-table
ob-exp org-macro org-footnote org-src ob-comint org-pcomplete org-list
org-faces org-entities noutline outline org-version ob-emacs-lisp
ob-core ob-eval org-table oc-basic bibtex iso8601 time-date ol org-keys
oc org-compat org-macs org-loaddefs format-spec find-func cal-menu
calendar cal-loaddefs edit-server advice smart-quotes easy-mmode
which-func imenu icomplete server term disp-table shell pcomplete ehelp
comint ansi-color ring hi-lock finder-inf rx info package browse-url url
url-proxy url-privacy url-expand url-methods url-history url-cookie
url-domsuf url-util mailcap url-handlers url-parse auth-source cl-seq
eieio eieio-core cl-macs eieio-loaddefs password-cache json subr-x map
url-vars seq byte-opt gv bytecomp byte-compile cconv cl-loaddefs cl-lib
iso-transl tooltip eldoc paren electric uniquify ediff-hook vc-hooks
lisp-float-type elisp-mode mwheel term/x-win x-win term/common-win x-dnd
tool-bar dnd fontset image regexp-opt fringe tabulated-list replace
newcomment text-mode lisp-mode prog-mode register page tab-bar menu-bar
rfn-eshadow isearch easymenu timer select scroll-bar mouse jit-lock
font-lock syntax font-core term/tty-colors frame minibuffer 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 composite emoji-zwj charscript
charprop case-table epa-hook jka-cmpr-hook help simple abbrev obarray
cl-preloaded nadvice button loaddefs faces cus-face macroexp files
window text-properties overlay sha1 md5 base64 format env code-pages
mule custom widget hashtable-print-readable backquote threads dbusbind
inotify dynamic-setting system-font-setting font-render-setting cairo
x-toolkit x multi-tty make-network-process native-compile emacs)

Memory information:
((conses 16 5075837 282334)
 (symbols 48 33785 6)
 (strings 32 224945 40322)
 (string-bytes 1 6976352)
 (vectors 16 78365)
 (vector-slots 8 2144723 316596)
 (floats 8 503 386)
 (intervals 56 367707 3813)
 (buffers 992 177))