How to fix a locale setting warning from Perl?

Question

When I run perl, I get the warning:

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
    LANGUAGE = (unset         


        

Answer 1

in my case, with debian8.6, i had to change settings in:

/etc/ssh/ssh_config for #AcceptEnv LANG LC_*

and sshd_config for #SendEnv LANG LC_*

then restart ssh service.

at last, did

locale-gen en_US.UTF-8 and dpkg-reconfigure locales

Answer 2

Your OS doesn't know about en_US.UTF-8.

You didn't mention a specific platform, but I can reproduce your problem:

% uname -a
OSF1 hunter2 V5.1 2650 alpha
% perl -e exit
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
    LC_ALL = (unset),
    LANG = "en_US.UTF-8"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").

My guess is you used ssh to connect to this older host from a newer desktop machine. It's common for /etc/ssh/sshd_config to contain

AcceptEnv LANG LC_*

which allows clients to propagate the values of those environment variables into new sessions.

The warning gives you a hint about how to squelch it if you don't require the full-up locale:

% env LANG=C perl -e exit
%

or with bash:

$ LANG=C perl -e exit
$ 

For a permanent fix, choose one of

1. On the older host, set the LANG environment variable in your shell's initialization file.
2. Modify your environment on the client side, e.g., rather than ssh hunter2, use the command LANG=C ssh hunter2.
3. If you have admin rights, stop ssh from sending the environment variables by commenting out the SendEnv LANG LC_* line in the local /etc/ssh/ssh_config file. (Thanks to this answer. See Bug 1285 for OpenSSH for more.)

Answer 3

Source of the problem

I experienced this, logging in from one machine to another via ssh. The remote machine didn’t have the locale files, that I had on my local machine. You can either disable the forwarding of the locale from your local machine to the remote machine (in the file /etc/ssh/sshd_config remove the line AcceptEnv LANG LC_CTYPE …) or install the locale (changing it is not necessary in this case).

Installing

On Fedora, RHEL, Redhat, CentOS I used

sudo dnf install langpacks-de

for the german (de) language packs. Logged out and in and it worked.

Search for other langpacks with

dnf search langpacks-

Changing/Activating

To list available locales I used

localectl list-locales

And to set a new one

sudo localectl set-locale de_DE.utf8

Answer 4

If you are creating a rootfs using debootstrap you will need to generate the locales. You can do this by running:

# (optional) enable missing locales
sudo nano /etc/locale.gen

# then regenerate
sudo locale-gen

This tip comes from, https://help.ubuntu.com/community/Xen

Answer 5

Adding the correct locale to ~/.bashrc, ~/.bash_profile, /etc/environment and the like will solve the problem, however it is not recommended, as it overrides the settings from /etc/default/locale, which is confusing at best and may lead to the locales not being applied consistently at worst.

Instead, one should edit /etc/default/locale directly, which may look something like this:

LANG=en_US.UTF-8
LANGUAGE=en_US:en
LC_CTYPE=en_US

The change will take effect the next time you log in. You can get the new locale in an existing shell by sourcing /etc/default/locale like this:

$ . /etc/default/locale

Answer 6

Add missing locales to .bash_profile

echo "export LANGUAGE=en_US.UTF-8
export LANG=en_US.UTF-8
export LC_ALL=en_US.UTF-8">>~/.bash_profile

Then source your .bash_profile

source ~/.bash_profile