Calling any executable which is not yet installed results in a message which is not easy to understand:
$ tcl
Der Befehl \xbbtcl\xab wurde nicht gefunden, meinten Sie vielleicht:
Befehl \xbbtel\xab aus dem Paket \xbborville-write\xab (universe)
Befehl \xbbtc\xab aus dem Paket \xbbiproute2\xab (main)
Befehl \xbbtcs\xab aus dem Paket \xbbtcs\xab (universe)
Befehl \xbbtjl\xab aus dem Paket \xbbpvm-examples\xab (universe)
Befehl \xbbcl\xab aus dem Paket \xbbcl-launch\xab (universe)
Befehl \xbbecl\xab aus dem Paket \xbbecl\xab (universe)
Befehl \xbbtcal\xab aus dem Paket \xbbgcal\xab (universe)
Befehl \xbbmcl\xab aus dem Paket \xbbmcl\xab (universe)
Befehl \xbbccl\xab aus dem Paket \xbbcclive\xab (universe)
Befehl \xbbtbl\xab aus dem Paket \xbbgroff-base\xab (main)
Befehl \xbbncl\xab aus dem Paket \xbbncl-ncarg\xab (universe)
Befehl \xbbgcl\xab aus dem Paket \xbbgcl\xab (universe)
Befehl \xbbtdl\xab aus dem Paket \xbbtdl\xab (universe)
Befehl \xbbtcc\xab aus dem Paket \xbbtcc\xab (universe)
Befehl \xbbtcm\xab aus dem Paket \xbbtcm\xab (universe)
tcl: Befehl nicht gefunden.
bogdanbiv@bivub1404:~$ which tcl
bogdanbiv@bivub1404:~$ hgjkh
hgjkh: Befehl nicht gefunden.
Also what's wrong with the hex characters (\xbb and \xab). My system is Kubuntu 14.04, trusty:
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.04.1 LTS
Release: 14.04
Codename: trusty
My system language is English, however I have some regional settings set for my country:
$ locale
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
LANG=en_RO.UTF-8
LANGUAGE=en:de:ro:en
LC_CTYPE="en_RO.UTF-8"
LC_NUMERIC=en_RO.UTF-8
LC_TIME=en_RO.UTF-8
LC_COLLATE="en_RO.UTF-8"
LC_MONETARY=en_RO.UTF-8
LC_MESSAGES="en_RO.UTF-8"
LC_PAPER=en_RO.UTF-8
LC_NAME=en_RO.UTF-8
LC_ADDRESS=en_RO.UTF-8
LC_TELEPHONE=en_RO.UTF-8
LC_MEASUREMENT=en_RO.UTF-8
LC_IDENTIFICATION=en_RO.UTF-8
LC_ALL=
Somehow I stumbled upon what may be some relevant information (see more at http://pastebin.com/4XGakzgL):
Command-not-found-Version: 0.3
Python-Version: 3.4.0 final 0
UPDATE: I tried various locale repair tools: a popup appeared saying I have incomplete language support and offered to help. That was nice, but it achieved nothing. Well, at least now, the messages in German are displayed correctly in UTF and forcing English does work:
$ LANGUAGE=en tcl
No command 'tcl' found, did you mean: # CORRECT, this should be normal behaviour
$ LANGUAGE=en:de:ro tcl
Der Befehl »tcl« wurde nicht gefunden, meinten Sie vielleicht: # This is German
Here is the output of locale
as of now:
LANG=en_GB.UTF-8
LANGUAGE=en:de:ro
LC_CTYPE="en_GB.UTF-8"
LC_NUMERIC=en_GB.UTF-8
LC_TIME=en_GB.UTF-8
LC_COLLATE="en_GB.UTF-8"
LC_MONETARY=en_GB.UTF-8
LC_MESSAGES=POSIX
LC_PAPER=en_GB.UTF-8
LC_NAME=en_GB.UTF-8
LC_ADDRESS=en_GB.UTF-8
LC_TELEPHONE=en_GB.UTF-8
LC_MEASUREMENT=en_GB.UTF-8
LC_IDENTIFICATION=en_GB.UTF-8
LC_ALL=
locale
say?locale
to the question proper.