On 2018-10-01 12:12:21 +0100, Adam D. Barratt wrote:
> On 2018-10-01 10:19, Vincent Lefevre wrote:
> > Package: exim4-config
> > Version: 4.91-8
> > Severity: grave
> > Justification: renders package unusable
> [...]
> > *** exim4.conf.template (Y/I/N/O/D/Z) [default=N] ? D
> > dpkg (subprocess): unable to execute conffile difference visualizer
> > (less -Lis): No such file or directory
> > dpkg: error processing package exim4-config (--configure):
> > conffile difference visualizer subprocess returned error exit status 2
>
> How is this possibly a bug in exim4-config? That package does not specify
> what command dpkg should use in order to page diffs.
>
> Looking at the dpkg source code, it first checks $PAGER and if that's not
> set falls back to running the "pager" executable. That suggests one of two
> things:
>
> - you have $PAGER set to "less -Lis" and for some reason don't have less
> available
It is set to "less -Lis", and I could check that it still works fine.
Note that I've used this value since December 2012 and had never had
any problem with it, including with the conffile difference visualizer:
the last time on this machine was on 2018-08-31, according to
/var/log/apt/term.log* files:
Log started: 2018-08-31 15:21:38
[...]
Installing new version of config file /etc/apparmor.d/abstractions/lightdm ...
Configuration file '/etc/lightdm/lightdm.conf'
==> Modified (by you or by a script) since installation.
==> Package distributor has shipped an updated version.
What would you like to do about it ? Your options are:
Y or I : install the package maintainer's version
N or O : keep your currently-installed version
D : show the differences between the versions
Z : start a shell to examine the situation
The default action is to keep your current version.
*** lightdm.conf (Y/I/N/O/D/Z) [default=N] ? D
[blank lines]
--- /etc/lightdm/lightdm.conf 2016-07-01 13:06:09.139950327 +0200
+++ /etc/lightdm/lightdm.conf.dpkg-new 2018-08-28 11:29:22.000000000 +0200
[...]
So, there doesn't seem to be anything wrong with my config.
> - your /usr/bin/pager alternative points to something that's not installed
> on your system.
Just in case, /usr/bin/pager works fine too (but since $PAGER is set,
this does not matter).
> 1) What is $PAGER set to in the environment in which you performed the
> upgrade?
less -Lis
> 2) What does /usr/bin/pager point to? (Please chase any symlinks to the
> ultmate endpoint)
/usr/bin/pager -> /etc/alternatives/pager
/etc/alternatives/pager -> /bin/less
> 3) How precisely did you invoke dpkg?
I used aptitude with its curses UI.
A possible bug might be that $PAGER is run as a program name,
instead of something like system(), which allows options.
--
Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
