Locale error messages

Locale error message

When you get errors like these examples - it is not obvious what causes it

$ rofi

(process:1628): Rofi-WARNING **: 07:34:43.942: Failed to set locale.

$ sterminal
couldn't read from shell: Input/output error
child exited with status 1
tmux: invalid LC_ALL, LC_CTYPE or LANG

Check your settings

Obviously you need to replace the locale with something relevant for your system. I have written this using my system's locale - en_DK for messages and da_DK for the rest of the system.

Check locale settings

$ localectl      
   System Locale: LANG=en_DK.UTF-8
                  LC_NUMERIC=da_DK.UTF-8
                  LC_TIME=da_DK.UTF-8
                  LC_MONETARY=da_DK.UTF-8
                  LC_PAPER=da_DK.UTF-8
                  LC_NAME=da_DK.UTF-8
                  LC_ADDRESS=da_DK.UTF-8
                  LC_TELEPHONE=da_DK.UTF-8
                  LC_MEASUREMENT=da_DK.UTF-8
                  LC_IDENTIFICATION=da_DK.UTF-8
       VC Keymap: dk-latin1
      X11 Layout: dk
       X11 Model: pc105

Check installed locales

$ locale -a
C
en_DK.utf8
en_US.utf8
POSIX

The installed locales does not match the settings listed by localectl - as you can see the da_DK part is missing.

Fix locale error

It is recommended to use the utf8 version unless you have compelling reasons to select otherwise.

Method 1

Edit /etc/locale.gen and ensure that all in-use locales has been uncommented. For fallback messages enable en_US as well

$ sudo nano /etc/locale.gen

...
#cy_GB ISO-8859-14  
da_DK.UTF-8 UTF-8  
#da_DK ISO-8859-1  
....
#en_CA ISO-8859-1  
en_DK.UTF-8 UTF-8  
#en_DK ISO-8859-1  
...
#en_SG ISO-8859-1  
en_US.UTF-8 UTF-8  
#en_US ISO-8859-1  
...

Method 2

Based on the comment by @nam1962 (see [2]).

Check if the locale you want to use is available in the locale list (/etc/locale.gen)

$ cat /etc/locale.gen | grep 'da_DK'
#da_DK.UTF-8 UTF-8  
#da_DK ISO-8859-1

Use sed command

To enable a locale (uncommenting the line)

$ sudo sed -i '/en_DK.UTF-8/s/^#//g' /etc/locale.gen
$ sudo sed -i '/en_US.UTF-8/s/^#//g' /etc/locale.gen

To disable a locale (aka commenting the locale)

$ sudo sed -i '/en_DK.UTF-8/s/^/#/g' /etc/locale.gen

Rebuild locales

$ sudo locale-gen
Generating locales...
  da_DK.UTF-8... done
  en_DK.UTF-8... done
  en_US.UTF-8... done
Generation complete.

Recheck your locales

$ locale -a      
C
da_DK.utf8
en_DK.utf8
en_US.utf8
POSIX

Verify it works

➜  ~ rofi -r
Rofi is unsure what to show.
Please specify the mode you want to show.

    rofi -show {mode}

The following modi are enabled:
 * window
 * run
 * ssh

The following can be enabled:
 * windowcd
 * drun
 * combi
 * keys

To activate a mode, add it to the list of modi in the modi setting.

Now it is fixed

Enjoy