当我想在OS X上安装Ruby 1.9.3时出现错误。我看到大部分问题都来自xCode未安装。所以，我安装了它，我仍然有问题，所以，这里是：
MacBook-Pro-de-Arnaud:~ Arnaud$ rvm install 1.9.3
Installing Ruby from source to: /Users/Arnaud/.rvm/rubies/ruby-1.9.3-p0, this may take a >while depending on your cpu(s)...
ruby-1.9.3-p0 - #fetching
ruby-1.9.3-p0 - #extracted to /Users/Arnaud/.rvm/src/ruby-1.9.3-p0 (already extracted)
Fetching yaml-0.1.4.tar.gz to /Users/Arnaud/.rvm/archives
Extracting yaml-0.1.4.tar.gz to /Users/Arnaud/.rvm/src
Configuring yaml in /Users/Arnaud/.rvm/src/yaml-0.1.4.
Compiling yaml in /Users/Arnaud/.rvm/src/yaml-0.1.4.
Installing yaml to /Users/Arnaud/.rvm/usr
ruby-1.9.3-p0 - #configuring
ERROR: Error running ' ./configure --prefix=/Users/Arnaud/.rvm/rubies/ruby-1.9.3-p0 --enable-shared --disable-install-doc --with-libyaml-dir=/Users/Arnaud/.rvm/usr ', please read /Users/Arnaud/.rvm/log/ruby-1.9.3-p0/configure.log
ERROR: There has been an error while running configure. Halting the installation.
所以，我决定让1.8.7并直接转到Rails并且安装似乎顺利，但没有什么是istall：/
MacBook-Pro-de-Arnaud:~ Arnaud$ sudo gem install rails
Password:
Successfully installed rails-3.1.3
1 gem installed
Installing ri documentation for rails-3.1.3...
Installing RDoc documentation for rails-3.1.3...
MacBook-Pro-de-Arnaud:~ Arnaud$ gem list
*** LOCAL GEMS ***
MacBook-Pro-de-Arnaud:~ Arnaud$ rail
-bash: rail: command not found
MacBook-Pro-de-Arnaud:~ Arnaud$ rails
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems.rb:777:in `report_activate_error': Could not find RubyGem rails (>= 0) (Gem::LoadError)
from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems.rb:211:in `activate'
from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems.rb:1056:in `gem'
from /usr/bin/rails:18
有人会有解决方案吗？