man pages won't get installed on 18.04 docker container

[kzidane]

For some reason man pages won't get installed on an 18.04 Docker container. Any idea what's causing this and how to fix? Thank you!

$ docker run -it --rm ubuntu:18.04
root@b1ec9717c001:/# apt-get update && apt-get install -y man-db
Get:1 http://security.ubuntu.com/ubuntu bionic-security InRelease [83.2 kB]
Get:2 http://archive.ubuntu.com/ubuntu bionic InRelease [242 kB]
Get:3 http://security.ubuntu.com/ubuntu bionic-security/universe Sources [4494 B]
Get:4 http://archive.ubuntu.com/ubuntu bionic-updates InRelease [83.2 kB]                     
Get:5 http://security.ubuntu.com/ubuntu bionic-security/main amd64 Packages [90.3 kB]
Get:6 http://security.ubuntu.com/ubuntu bionic-security/multiverse amd64 Packages [1066 B]
Get:7 http://security.ubuntu.com/ubuntu bionic-security/universe amd64 Packages [22.7 kB]               
Get:8 http://archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]                              
Get:9 http://archive.ubuntu.com/ubuntu bionic/universe Sources [11.5 MB]                                              
Get:10 http://archive.ubuntu.com/ubuntu bionic/restricted amd64 Packages [13.5 kB]
Get:11 http://archive.ubuntu.com/ubuntu bionic/multiverse amd64 Packages [186 kB]
Get:12 http://archive.ubuntu.com/ubuntu bionic/main amd64 Packages [1344 kB]
Get:13 http://archive.ubuntu.com/ubuntu bionic/universe amd64 Packages [11.3 MB]
Get:14 http://archive.ubuntu.com/ubuntu bionic-updates/universe Sources [29.4 kB]
Get:15 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 Packages [140 kB]
Get:16 http://archive.ubuntu.com/ubuntu bionic-updates/multiverse amd64 Packages [1660 B]
Get:17 http://archive.ubuntu.com/ubuntu bionic-updates/universe amd64 Packages [85.0 kB]
Get:18 http://archive.ubuntu.com/ubuntu bionic-backports/universe amd64 Packages [2786 B]
Fetched 25.3 MB in 3s (8834 kB/s)                         
Reading package lists... Done
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  bsdmainutils groff-base libbsd0 libgdbm5 libpipeline1
Suggested packages:
  cpp wamerican | wordlist whois vacation groff gdbm-l10n apparmor less www-browser
The following NEW packages will be installed:
  bsdmainutils groff-base libbsd0 libgdbm5 libpipeline1 man-db
0 upgraded, 6 newly installed, 0 to remove and 16 not upgraded.
Need to get 2446 kB of archives.
After this operation, 6788 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu bionic/main amd64 libbsd0 amd64 0.8.7-1 [41.5 kB]
Get:2 http://archive.ubuntu.com/ubuntu bionic/main amd64 bsdmainutils amd64 11.1.2ubuntu1 [181 kB]
Get:3 http://archive.ubuntu.com/ubuntu bionic/main amd64 groff-base amd64 1.22.3-10 [1153 kB]
Get:4 http://archive.ubuntu.com/ubuntu bionic/main amd64 libgdbm5 amd64 1.14.1-6 [26.0 kB]
Get:5 http://archive.ubuntu.com/ubuntu bionic/main amd64 libpipeline1 amd64 1.5.0-1 [25.3 kB]
Get:6 http://archive.ubuntu.com/ubuntu bionic/main amd64 man-db amd64 2.8.3-2 [1019 kB]
Fetched 2446 kB in 1s (2005 kB/s)
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package libbsd0:amd64.
(Reading database ... 4035 files and directories currently installed.)
Preparing to unpack .../0-libbsd0_0.8.7-1_amd64.deb ...
Unpacking libbsd0:amd64 (0.8.7-1) ...
Selecting previously unselected package bsdmainutils.
Preparing to unpack .../1-bsdmainutils_11.1.2ubuntu1_amd64.deb ...
Unpacking bsdmainutils (11.1.2ubuntu1) ...
Selecting previously unselected package groff-base.
Preparing to unpack .../2-groff-base_1.22.3-10_amd64.deb ...
Unpacking groff-base (1.22.3-10) ...
Selecting previously unselected package libgdbm5:amd64.
Preparing to unpack .../3-libgdbm5_1.14.1-6_amd64.deb ...
Unpacking libgdbm5:amd64 (1.14.1-6) ...
Selecting previously unselected package libpipeline1:amd64.
Preparing to unpack .../4-libpipeline1_1.5.0-1_amd64.deb ...
Unpacking libpipeline1:amd64 (1.5.0-1) ...
Selecting previously unselected package man-db.
Preparing to unpack .../5-man-db_2.8.3-2_amd64.deb ...
Unpacking man-db (2.8.3-2) ...
Setting up groff-base (1.22.3-10) ...
Setting up libpipeline1:amd64 (1.5.0-1) ...
Setting up libgdbm5:amd64 (1.14.1-6) ...
Setting up libbsd0:amd64 (0.8.7-1) ...
Processing triggers for libc-bin (2.27-3ubuntu1) ...
Setting up bsdmainutils (11.1.2ubuntu1) ...
update-alternatives: using /usr/bin/bsd-write to provide /usr/bin/write (write) in auto mode
update-alternatives: warning: skip creation of /usr/share/man/man1/write.1.gz because associated file /usr/share/man/man1/bsd-write.1.gz (of link group write) doesn't exist
update-alternatives: using /usr/bin/bsd-from to provide /usr/bin/from (from) in auto mode
update-alternatives: warning: skip creation of /usr/share/man/man1/from.1.gz because associated file /usr/share/man/man1/bsd-from.1.gz (of link group from) doesn't exist
Setting up man-db (2.8.3-2) ...
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 76.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.26.1 /usr/local/share/perl/5.26.1 /usr/lib/x86_64-linux-gnu/perl5/5.26 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.26 /usr/share/perl/5.26 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype
Building database of manual pages ...
root@b1ec9717c001:/# man man
No manual entry for man
See 'man 7 undocumented' for help when manual pages are not available.
root@b1ec9717c001:/# 

[kzidane]

It appears they're excluded by /etc/dpkg/dpkg.cfg.d/excludes:

$ cat /etc/dpkg/dpkg.cfg.d/excludes
# Drop all man pages
path-exclude=/usr/share/man/*

# Drop all documentation ...
path-exclude=/usr/share/doc/*

# ... except copyright files ...
path-include=/usr/share/doc/*/copyright

# ... and Debian changelogs
path-include=/usr/share/doc/*/changelog.Debian.*

Commenting the path-exclude lines seems to fix the problem. Any reason why they're excluded?

[tianon]

See #122.