（我已经安装了systemd-coredump）
向什么发送QUIT信号debconf-communicate？
由于回溯不包括raise()/ ，我想我可以假设这个致命信号是由其他正在运行的程序kill()发送的？debconf-communicate
man 7 signal说该信号QUIT最初是用于“从键盘退出”。与信号（“键盘中断”）的区别INT在于QUIT故意转储核心。据推测这是一种调试技术。 SIGINT通过组合键 Ctrl+C 发送。 SIGQUIT通过 Ctrl+\ 发送。
apt然而，我似乎在没有人在终端中运行的命令上按 Ctrl+\ 的情况下获取这些核心转储。当使用 PackageKit 进行软件包升级时，似乎会发生（有时？）。
这是 Debian 9 桌面系统 (GNOME)。我不知道发生此崩溃时会发生什么，除了说用户没有报告任何问题:-)。主要用户通常擅长应用更新，并了解其重要性。
由于 Debian中的bug 过去未能发送更新通知，系统目前除了通常pk-update-icon的..desktopgnome-packagekitgpk-update-viewergnome-software
$ dpkg-query -l packagekit gnome-software gnome-packagekit pk-update-icon debconf dpkg apt
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-====================-===============-===============-==============================================
ii apt 1.4.9 amd64 commandline package manager
ii debconf 1.5.61 all Debian configuration management system
ii dpkg 1.18.25 amd64 Debian package management system
ii gnome-packagekit 3.22.1-2 amd64 Graphical distribution neutral package manager
ii gnome-software 3.22.5-1 amd64 Software Center for GNOME
ii packagekit 1.1.5-2+deb9u1 amd64 Provides a package management service
ii pk-update-icon 2.0.0-2 amd64 Displays an update-notification tray icon
$ sudo coredumpctl --no-pager
TIME PID UID GID SIG COREFILE EXE
Thu 2018-07-12 10:13:09 BST 5059 1005 1009 3 missing /usr/bin/perl
Sat 2018-07-14 11:16:38 BST 2346 1005 1009 3 missing /usr/bin/perl
...
Wed 2019-05-22 14:35:32 BST 2535 1005 1009 3 missing /usr/bin/perl
Thu 2019-05-23 11:39:52 BST 2311 1005 1009 3 missing /usr/bin/perl
Sat 2019-05-25 10:16:47 BST 2445 1005 1009 3 missing /usr/bin/perl
Thu 2019-05-30 08:16:50 BST 2497 1005 1009 3 missing /usr/bin/perl
Fri 2019-05-31 11:10:27 BST 2404 1005 1009 3 missing /usr/bin/perl
Thu 2019-06-06 15:47:50 BST 4282 1005 1009 3 missing /usr/bin/perl
Fri 2019-06-07 10:16:49 BST 2640 1005 1009 3 missing /usr/bin/perl
$ sudo coredumpctl info 2640
PID: 2640 (debconf-communi)
UID: 1005 (YYY)
GID: 1009 (YYY)
Signal: 3 (QUIT)
Timestamp: Fri 2019-06-07 10:16:49 BST (4 days ago)
Command Line: /usr/bin/perl -w /usr/bin/debconf-communicate
Executable: /usr/bin/perl
Control Group: /user.slice/user-1005.slice/session-2.scope
Unit: session-2.scope
Slice: user-1005.slice
Session: 2
Owner UID: 1005 (YYY)
Boot ID: 37f2efd8086a42b5a39144b5411b1523
Machine ID: 35fb9280fa2847946f17a060542fd617
Hostname: drystone
Storage: /var/lib/systemd/coredump/core.debconf-communi.1005.37f2efd8086a42b5a39144b5411b1523.2640.1559899009000000000000.lz4 (inaccessible)
Message: Process 2640 (debconf-communi) of user 1005 dumped core.
Stack trace of thread 2640:
#0 0x00007fa8db86a210 read (libpthread.so.0)
#1 0x00005598354afa7d PerlIOUnix_read (perl)
#2 0x00005598354b2fcf PerlIOBuf_fill (perl)
#3 0x00005598354b1658 Perl_PerlIO_fill (perl)
#4 0x00005598354b2e80 PerlIOBase_read (perl)
#5 0x00005598354b4e08 PerlIO_getc (perl)
#6 0x000055983544b2a5 Perl_sv_gets (perl)
#7 0x000055983542d376 Perl_do_readline (perl)
#8 0x0000559835428aa6 Perl_runops_standard (perl)
#9 0x00005598353ae8a9 perl_run (perl)
#10 0x0000559835387a5d main (perl)
#11 0x00007fa8db4db2e1 __libc_start_main (libc.so.6)
#12 0x0000559835387a9a _start (perl)
$ sudo journalctl --since="2019-06-07"
...
Jun 07 10:16:05 drystone PackageKit[1359]: get-updates transaction /21666_bacedcbd from uid 1005 finished with success after 657ms
Jun 07 10:16:09 drystone PackageKit[1359]: new update-packages transaction /21669_aeeccbac scheduled from uid 1005
Jun 07 10:16:10 drystone PackageKit[1359]: get-update-detail transaction /21667_cebbebab from uid 1005 finished with success after 5406ms
Jun 07 10:16:11 drystone PackageKit[1359]: get-details transaction /21668_dabdcebe from uid 1005 finished with success after 395ms
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package evolution;3.22.6-1+deb9u2;amd64;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package evolution-common;3.22.6-1+deb9u2;all;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package evolution-plugins;3.22.6-1+deb9u2;amd64;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package libevolution;3.22.6-1+deb9u2;amd64;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package qemu-kvm;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package qemu-system-common;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package qemu-system-x86;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: in /21669_aeeccbac for update-packages package qemu-utils;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was updating for uid 1005
Jun 07 10:16:11 drystone PackageKit[1359]: update-packages transaction /21669_aeeccbac from uid 1005 finished with success after 585ms
Jun 07 10:16:11 drystone PackageKit[1359]: uid 1005 is trying to obtain org.freedesktop.packagekit.system-update auth (only_trusted:1)
Jun 07 10:16:11 drystone gnome-shell[1769]: JS LOG: polkitAuthenticationAgent: Received 2 identities that can be used for authentication. Only considering one.
Jun 07 10:16:16 drystone polkitd(authority=local)[589]: Operator of unix-session:2 successfully authenticated as unix-user:YYY to gain TEMPORARY authorization for action org.freedesktop.packagekit.system-update
Jun 07 10:16:16 drystone PackageKit[1359]: new update-packages transaction /21670_adbeabac scheduled from uid 1005
Jun 07 10:16:16 drystone PackageKit[1359]: uid 1005 obtained auth for org.freedesktop.packagekit.system-update
Jun 07 10:16:38 drystone packagekitd[1359]: PARENT process running...
Jun 07 10:16:41 drystone gnome-software-service.desktop[1906]: 09:16:41:0610 As failed to rescan: No valid root node specified
Jun 07 10:16:41 drystone gnome-software-service.desktop[1906]: 09:16:41:0617 As failed to rescan: Failed to parse /usr/share/applications/evolution.desktop file: cannot process file of type application/x-deskto
Jun 07 10:16:41 drystone gnome-software-service.desktop[1906]: 09:16:41:0642 As failed to rescan: No valid root node specified
Jun 07 10:16:41 drystone gnome-software-service.desktop[1906]: 09:16:41:0646 As failed to rescan: Failed to parse /usr/share/applications/evolution.desktop.dpkg-tmp file: cannot process file of type text/plain
Jun 07 10:16:42 drystone gnome-software-service.desktop[1906]: 09:16:42:0406 As failed to rescan: No valid root node specified
Jun 07 10:16:42 drystone gnome-software-service.desktop[1906]: 09:16:42:0410 As failed to rescan: No valid root node specified
Jun 07 10:16:42 drystone gnome-software-service.desktop[1906]: 09:16:42:0410 As failed to rescan: No valid root node specified
Jun 07 10:16:42 drystone gnome-software-service.desktop[1906]: 09:16:42:0414 As failed to rescan: No valid root node specified
Jun 07 10:16:42 drystone gnome-software-service.desktop[1906]: 09:16:42:0414 As failed to rescan: No valid root node specified
Jun 07 10:16:44 drystone gnome-software-service.desktop[1906]: 09:16:44:0075 As failed to rescan: No valid root node specified
Jun 07 10:16:44 drystone gnome-software-service.desktop[1906]: 09:16:44:0078 As failed to rescan: No valid root node specified
Jun 07 10:16:44 drystone gnome-software-service.desktop[1906]: 09:16:44:0082 As failed to rescan: No valid root node specified
Jun 07 10:16:49 drystone packagekitd[1359]: Parent finished...
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-system-common;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package evolution-plugins;3.22.6-1+deb9u2;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package evolution;3.22.6-1+deb9u2;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package libevolution;3.22.6-1+deb9u2;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package evolution-common;3.22.6-1+deb9u2;all;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-kvm;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-system-x86;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-utils;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package evolution-common;3.22.6-1+deb9u2;all;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package libglib2.0-0;2.50.3-2;amd64;installed:debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-utils;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package libevolution;3.22.6-1+deb9u2;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-system-common;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-system-x86;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package evolution;3.22.6-1+deb9u2;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package evolution-plugins;3.22.6-1+deb9u2;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: in /21670_adbeabac for update-packages package qemu-kvm;1:2.8+dfsg-6+deb9u7;amd64;debian-stable-main was installing for uid 1005
Jun 07 10:16:49 drystone PackageKit[1359]: update-packages transaction /21670_adbeabac from uid 1005 finished with success after 33545ms
Jun 07 10:16:49 drystone gpk-update-view[2476]: Source ID 1825 was not found when attempting to remove it
Jun 07 10:16:49 drystone systemd[1]: Created slice system-systemd\x2dcoredump.slice.
Jun 07 10:16:49 drystone systemd[1]: Started Process Core Dump (PID 3620/UID 0).
Jun 07 10:16:49 drystone systemd-coredump[3621]: Process 2640 (debconf-communi) of user 1005 dumped core.
Stack trace of thread 2640:
#0 0x00007fa8db86a210 read (libpthread.so.0)
#1 0x00005598354afa7d PerlIOUnix_read (perl)
#2 0x00005598354b2fcf PerlIOBuf_fill (perl)
#3 0x00005598354b1658 Perl_PerlIO_fill (perl)
#4 0x00005598354b2e80 PerlIOBase_read (perl)
#5 0x00005598354b4e08 PerlIO_getc (perl)
#6 0x000055983544b2a5 Perl_sv_gets (perl)
#7 0x000055983542d376 Perl_do_readline (perl)
#8 0x0000559835428aa6 Perl_runops_standard (perl)
#9 0x00005598353ae8a9 perl_run (perl)
#10 0x0000559835387a5d main (perl)
#11 0x00007fa8db4db2e1 __libc_start_main (libc.so.6)
#12 0x0000559835387a9a _start (perl)
Jun 07 10:16:50 drystone PackageKit[1359]: get-updates transaction /21671_baceadea from uid 1005 finished with success after 597ms
Jun 07 10:16:50 drystone gpk-update-view[2476]: gtk_widget_hide: assertion 'GTK_IS_WIDGET (widget)' failed
Jun 07 10:16:52 drystone PackageKit[1359]: get-updates transaction /21672_cdcdcbca from uid 1005 finished with success after 884ms
Jun 07 10:16:52 drystone gpk-update-view[2476]: gtk_widget_hide: assertion 'GTK_IS_WIDGET (widget)' failed
Jun 07 10:16:55 drystone gpk-update-view[2476]: g_application_release: assertion 'application->priv->use_count > 0' failed
Jun 07 10:16:57 drystone PackageKit[1359]: get-updates transaction /21673_bdabdecd from uid 1005 finished with success after 638ms
Jun 07 10:17:01 drystone CRON[3642]: pam_env(cron:session): Unable to open env file: /etc/environment: No such file or directory
Jun 07 10:17:01 drystone CRON[3642]: pam_unix(cron:session): session opened for user root by (uid=0)
Jun 07 10:17:01 drystone CRON[3643]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jun 07 10:17:01 drystone CRON[3642]: pam_unix(cron:session): session closed for user root
Jun 07 10:24:14 drystone systemd[1]: Starting Cleanup of Temporary Directories...
Jun 07 10:24:14 drystone systemd[1]: Started Cleanup of Temporary Directories.
答案1
https://github.com/hughsie/PackageKit/blob/PACKAGEKIT_1_1_5/NEWS#L6157
~ 版本 0.1.1 ~ 发布时间: 2007-10-23
[...]
新功能：
[...]
- 发送
SIGQUIT然后SIGKILL稍微延迟一下，这样我们就可以通过解锁来很好地清理后端当我们取消时（理查德·休斯）