mac system environment variables

a. /etc/profile 
b. /etc/paths 
c. ~/.bash_profile 
d. ~/.bash_login 
e. ~/.profile 
f. ~/.bashrc 

Wherein a and b are 系统级别, the system will start loading, the user is connected to the remaining other. 
c, d, e in accordance with the front to back 顺序读取, if c file exists, the next few documents will be ignored 不读了, and so on. 
~ / .bashrc no such rule, it is loaded bash shell when opened.