debian でロケールのエラーが出るときの対処法

アップデートなどで以下のようなエラーが出る時の対処方法

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
    LANGUAGE = (unset),
    LC_ALL = (unset),
    LC_CTYPE = "UTF-8",
    LANG = "en_US"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
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

対処方法

以下の通り実行

export LANG=en_US.UTF-8
export LC_ALL=$LANG
locale-gen --purge $LANG
dpkg-reconfigure -f noninteractive locales && /usr/sbin/update-locale LANG=$LANG LC_ALL=$LANG