Comment 8 for bug 1802958

On trusty :

- apt install ghostscript, upgrades only ghostscript and libgs9 but NOT libgs9-common :

jo@trusty-build:~$ dpkg -l | grep ghostscript
ii ghostscript 9.25~dfsg+1-0ubuntu0.14.04.1 amd64 interpreter for the PostScript language and for PDF
jo@trusty-build:~$ dpkg -l | grep libgs9
ii libgs9 9.25~dfsg+1-0ubuntu0.14.04.1 amd64 interpreter for the PostScript language and for PDF - Library
ii libgs9-common 9.25~dfsg+1-0ubuntu0.14.04.1 all interpreter for the PostScript language and for PDF - common files
jo@trusty-build:~$ sudo apt install ghostscript
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
  libgs9
Suggested packages:
  ghostscript-x hpijs
The following packages will be upgraded:
  ghostscript libgs9
2 upgraded, 0 newly installed, 0 to remove and 18 not upgraded.
Need to get 0 B/2,392 kB of archives.
After this operation, 4,096 B of additional disk space will be used.
Do you want to continue? [Y/n] Y
(Reading database ... 31580 files and directories currently installed.)
Preparing to unpack .../ghostscript_9.25~dfsg+1-0ubuntu0.14.04.2_amd64.deb ...
Unpacking ghostscript (9.25~dfsg+1-0ubuntu0.14.04.2) over (9.25~dfsg+1-0ubuntu0.14.04.1) ...
Preparing to unpack .../libgs9_9.25~dfsg+1-0ubuntu0.14.04.2_amd64.deb ...
Unpacking libgs9 (9.25~dfsg+1-0ubuntu0.14.04.2) over (9.25~dfsg+1-0ubuntu0.14.04.1) ...
Processing triggers for man-db (2.6.7.1-1ubuntu1) ...
Setting up libgs9 (9.25~dfsg+1-0ubuntu0.14.04.2) ...
Setting up ghostscript (9.25~dfsg+1-0ubuntu0.14.04.2) ...
Processing triggers for libc-bin (2.19-0ubuntu6.14) ...
jo@trusty-build:~$ dpkg -l | grep ghostscript
ii ghostscript 9.25~dfsg+1-0ubuntu0.14.04.2 amd64 interpreter for the PostScript language and for PDF
jo@trusty-build:~$ dpkg -l | grep libgs9
ii libgs9 9.25~dfsg+1-0ubuntu0.14.04.2 amd64 interpreter for the PostScript language and for PDF - Library
ii libgs9-common 9.25~dfsg+1-0ubuntu0.14.04.1 all interpreter for the PostScript language and for PDF - common files

- After upgrade ghostscript from -proposed, ghostscript, libgs9 and libgs9-common at right version :

jo@trusty-build:~$ sudo apt-get install ghostscript/trusty-proposed
Reading package lists... Done
Building dependency tree
Reading state information... Done
Selected version '9.25~dfsg+1-0ubuntu0.14.04.3' (Ubuntu:14.04/trusty-proposed [amd64]) for 'ghostscript'
Selected version '9.25~dfsg+1-0ubuntu0.14.04.3' (Ubuntu:14.04/trusty-proposed [amd64]) for 'libgs9' because of 'ghostscript'
Selected version '9.25~dfsg+1-0ubuntu0.14.04.3' (Ubuntu:14.04/trusty-proposed [all]) for 'libgs9-common' because of 'libgs9'
The following extra packages will be installed:
  libgs9 libgs9-common
Suggested packages:
  ghostscript-x hpijs fonts-droid
The following packages will be upgraded:
  ghostscript libgs9 libgs9-common
3 upgraded, 0 newly installed, 0 to remove and 17 not upgraded.
Need to get 7,489 kB of archives.
After this operation, 8,192 B of additional disk space will be used.
Do you want to continue? [Y/n] Y
Get:1 http://archive.ubuntu.com/ubuntu/ trusty-proposed/main libgs9-common all 9.25~dfsg+1-0ubuntu0.14.04.3 [5,096 kB]
Get:2 http://archive.ubuntu.com/ubuntu/ trusty-proposed/main ghostscript amd64 9.25~dfsg+1-0ubuntu0.14.04.3 [47.2 kB]
Get:3 http://archive.ubuntu.com/ubuntu/ trusty-proposed/main libgs9 amd64 9.25~dfsg+1-0ubuntu0.14.04.3 [2,346 kB]
Fetched 7,489 kB in 9s (797 kB/s)
(Reading database ... 31789 files and directories currently installed.)
Preparing to unpack .../libgs9-common_9.25~dfsg+1-0ubuntu0.14.04.3_all.deb ...
Unpacking libgs9-common (9.25~dfsg+1-0ubuntu0.14.04.3) over (9.25~dfsg+1-0ubuntu0.14.04.1) ...
Preparing to unpack .../ghostscript_9.25~dfsg+1-0ubuntu0.14.04.3_amd64.deb ...
Unpacking ghostscript (9.25~dfsg+1-0ubuntu0.14.04.3) over (9.25~dfsg+1-0ubuntu0.14.04.2) ...
Preparing to unpack .../libgs9_9.25~dfsg+1-0ubuntu0.14.04.3_amd64.deb ...
Unpacking libgs9 (9.25~dfsg+1-0ubuntu0.14.04.3) over (9.25~dfsg+1-0ubuntu0.14.04.2) ...
Processing triggers for man-db (2.6.7.1-1ubuntu1) ...
Setting up libgs9-common (9.25~dfsg+1-0ubuntu0.14.04.3) ...
Setting up libgs9 (9.25~dfsg+1-0ubuntu0.14.04.3) ...
Setting up ghostscript (9.25~dfsg+1-0ubuntu0.14.04.3) ...
Processing triggers for libc-bin (2.19-0ubuntu6.14) ...
jo@trusty-build:~$ dpkg -l | grep ghostscript
ii ghostscript 9.25~dfsg+1-0ubuntu0.14.04.3 amd64 interpreter for the PostScript language and for PDF
jo@trusty-build:~$ dpkg -l | grep libgs9
ii libgs9 9.25~dfsg+1-0ubuntu0.14.04.3 amd64 interpreter for the PostScript language and for PDF - Library
ii libgs9-common 9.25~dfsg+1-0ubuntu0.14.04.3 all interpreter for the PostScript language and for PDF - common files