$ sudo apt install nkf
Result:
[sudo] password for USERNAME:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
linux-headers-4.4.0-21 linux-headers-4.4.0-21-generic linux-headers-4.4.0-22 linux-headers-4.4.0-22-generic linux-image-4.4.0-21-generic linux-image-4.4.0-22-generic
linux-image-extra-4.4.0-21-generic linux-image-extra-4.4.0-22-generic
Use 'sudo apt autoremove' to remove them.
The following NEW packages will be installed:
nkf
0 upgraded, 1 newly installed, 0 to remove and 55 not upgraded.
Need to get 126 kB of archives.
After this operation, 308 kB of additional disk space will be used.
Get:1 http://jp.archive.ubuntu.com/ubuntu xenial/universe amd64 nkf amd64 2.13-4build1 [126 kB]
Fetched 126 kB in 0s (879 kB/s)
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LC_CTYPE = "UTF-8",
LANG = "ja_JP.UTF-8"
are supported and installed on your system.
perl: warning: Falling back to a fallback locale ("ja_JP.UTF-8").
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: LC_ALL??????????????????: ??????????????????????
Selecting previously unselected package nkf.
(Reading database ... 189320 files and directories currently installed.)
Preparing to unpack .../nkf_2.13-4build1_amd64.deb ...
Unpacking nkf (2.13-4build1) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up nkf (2.13-4build1) ...