Why does Rails console say "cannot load such file -- readline"?

Question

I am new to Ruby on Rails, and am using RVM to manage Ruby versions. My laptop has Ruby1.8.7 installed, but my project is using RVM, Ruby1.9.3 and Rails 3.2.11. I can't run `rails c` or `rails console` without it giving me the following error: ``` /home/phil/.rvm/rubies/ruby-1.9.3-p392/lib/ruby/1.9.1/irb/completion.rb:9:in `require': cannot load such file -- readline (LoadError) from /home/phil/.rvm/rubies/ruby-1.9.3-p392/lib/ruby/1.9.1/irb/completion.rb:9:in `' from /home/phil/.rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.11/lib/rails/commands/console.rb:3:in `require' from /home/phil/.rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.11/lib/rails/commands/console.rb:3:in `' from /home/phil/.rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.11/lib/rails/commands.rb:38:in `require' from /home/phil/.rvm/gems/ruby-1.9.3-p392/gems/railties-3.2.11/lib/rails/commands.rb:38:in `' from script/rails:6:in `require' from script/rails:6:in `

' ```

Accepted Answer

You need to have the readline libraries installed when you compile Ruby.

If you are on CentOS/Redhat/Fedora Linux, install the package using:

```
sudo yum install readline-devel
```

Or, on Ubuntu, use:

```
sudo apt-get install libreadline6 libreadline6-dev
```

and then recompile Ruby.

Why does Rails console say "cannot load such file -- readline"?

Solution

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