Ubuntu 11 Raylar yüklerken bu sorun var: ben

root@salah:/home/salah/rubygems-1.8.15# sudo gem install mysql

Fetching: mysql-2.8.1.gem (100%)
Building native extensions.  This could take a while...
ERROR:  Error installing mysql:
    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:10:in `<main>'


Gem files will remain installed in /usr/lib/ruby/gems/1.9.1/gems/mysql-2.8.1 for inspection.
Results logged to /usr/lib/ruby/gems/1.9.1/gems/mysql-2.8.1/ext/mysql_api/gem_make.out

Ubuntu 13.04 için, bu benim için çalıştı budur:

sudo apt-get install ruby-dev