Centos默认自带VI，功能没VIM丰富，安装VIM取代VI。
用Yum查找源中的VIM包，不知安装哪个合适。
yum search vim
vim-X11.i386 : The VIM version of the vi editor for the X Window System.
vim-common.i386 : The common files needed by any version of the VIM editor.
vim-enhanced.i386 : A version of the VIM editor which includes recent enhancements.
vim-minimal.i386 : A minimal version of the VIM editor.到已安装VIM的系统中查看VIM属于哪个软件包：
which vim
/usr/bin/vim
rpm -qf /usr/bin/vim
vim-enhanced-7.0.109-7.el5安装VIM：
yum install vim-enhanced