Linux下手动下载安装ruby/rubygems/rails

1,ruby

download ruby-1.8.6.tar.gz
tar zxvf ruby-1.8.6.tar.gz
./configure
sudo make
sudo make install

2,rubygems

download rubygems-0.9.2.tgz
tar zxvf rubygems-0.9.2.tgz
sudo ruby setup.rb

3,rails

sudo gem install rails -y