在Ubuntu上安装的Rails无法加载mkmf？

Question

我正在尝试在Ubuntu上安装Rails:

sudo gem install rails

但我遇到了麻烦:

Building native extensions.  This could take a while...
ERROR:  Error installing rails:
  ERROR: Failed to build gem native extension.

        /usr/bin/ruby1.9.1 extconf.rb
/usr/local/lib/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- mkmf (LoadError)
  from /usr/local/lib/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
  from extconf.rb:1:in `<main>'


Gem files will remain installed in /usr/lib/ruby/gems/1.9.1/gems/json-1.7.7 for inspection.
Results logged to /usr/lib/ruby/gems/1.9.1/gems/json-1.7.7/ext/json/ext/generator/gem_make.out

问题是什么？

Answer 1

丹尼尔在评论中说,尝试并执行 sudo apt-get install ruby-dev