On Wed, Feb 6, 2013 at 7:50 AM, Efe A. <lists / ruby-forum.com> wrote:
> When i try to install rails in Ubuntu 12.10 i get this error:
>
> [CODE]    $ gem install rails
>     ERROR: Loading command: install (LoadError)
>     cannot load such file -- zlib
>     ERROR: While executing gem ... (NameError)
>     uninitialized constant Gem::Commands::InstallCommand[/CODE]

Did you run `rvm requirements`? I know I recently had the same
trouble, and the requirements list led me to install the right Ubuntu
packages. I don't recall offhand if it only required zlib1g-dev and
zlib1g, or if something else was required; but I didn't have to use
`rvm pkg` at all once I had the debs installed.