再設置java 或者其他環境變量的時候，網上建議大多設置profile但是查看centos6.5的profile 文件我發現專家是有建議的就是這個 原文
cat profile
# /etc/profile
# System wide environment and startup programs, for login setup
# Functions and aliases go in /etc/bashrc
# It's NOT a good idea to change this file unless you know what you
# are doing. It's much better to create a custom.sh shell script in
# /etc/profile.d/ to make custom changes to your environment, as this
# will prevent the need for merging in future updates.
記下來 避免以後再忘記