Setting environment variables on OS X

Question

What is the proper way to modify environment variables like PATH in OS X?

I\'ve looked on Google a little bit and found three different files to edit:

Answer 1

Login Shells

/etc/profile

The shell first executes the commands in file /etc/profile. A user working with root privileges can set up this file to establish systemwide default characteristics for users running Bash.

.bash_profile
.bash_login
.profile

Next the shell looks for ~/.bash_profile, ~/.bash_login, and ~/.profile (~/ is short- hand for your home directory), in that order, executing the commands in the first of these files it finds. You can put commands in one of these files to override the defaults set in /etc/profile. A shell running on a virtual terminal does not execute commands in these files.

.bash_logout

When you log out, bash executes commands in the ~/.bash_logout file. This file often holds commands that clean up after a session, such as those that remove temporary files.

Interactive Nonlogin Shells

/etc/bashrc

Although not called by bash directly, many ~/.bashrc files call /etc/bashrc. This setup allows a user working with root privileges to establish systemwide default characteristics for nonlogin bash shells.

.bashrc

An interactive nonlogin shell executes commands in the ~/.bashrc file. Typically a startup file for a login shell, such as .bash_profile, runs this file, so both login and nonlogin shells run the commands in .bashrc.

Because commands in .bashrc may be executed many times, and because subshells inherit exported variables, it is a good idea to put commands that add to existing variables in the .bash_profile file.