Run update.sh

ruby/README.md

@@ -62,6 +62,10 @@ For many simple, single file projects, you may find it inconvenient to write a c
 $ docker run -it --rm --name my-running-script -v "$PWD":/usr/src/myapp -w /usr/src/myapp ruby:2.1 ruby your-daemon-or-script.rb
 ```
 
+## Encoding
+
+By default, Ruby inherits the locale of the environment in which it is run. For most users running Ruby on their desktop systems, that means it's likely using some variation of `*.UTF-8` (`en_US.UTF-8`, etc). In Docker however, the default locale is `C`, which can have unexpected results. If your application needs to interact with UTF-8, it is recommended that you explicitly adjust the locale of your image/container via `-e LANG=C.UTF-8` or `ENV LANG C.UTF-8`.
+
 # Image Variants
 
 The `ruby` images come in many flavors, each designed for a specific use case.