Hi guys, my first post
I have a problem installing rails
Building native extensions. This could take a while...
ERROR: Error installing rails:
ERROR: Failed to build gem native extension.
extconf.rb:36:in `require': no such file to load -- mkmf (LoadError)
from extconf.rb:36:in `<main>'
Gem files will remain installed in /usr/lib/ruby/gems/1.9.1/gems/
bcrypt-ruby-3.0.1 for inspection.
Results logged to /usr/lib/ruby/gems/1.9.1/gems/bcrypt-ruby-3.0.1/ext/
someone help me ..
Thank you very much