Set environment variables on Mac OS X Lion

When someone says "edit your .plist file" or "your .profile" or ".bash_profile" etc, this just confuses me. I have no idea where these files are, how to create them if I have to do that, etc, and also why there seem to be so many different ones (why? Do they do different things?)

So could someone please explain very patiently to a previous Windows user (wanting desperately to become more familiar with the pleasant if initially somewhat confusing OS X world) how to do this step by step?

I need the variables to be set both for GUI applications and command line applications, and at the moment it's for an ant script that needs the variables, but there will most likely be other needs as well.

Please note that I have Lion too, since many of the answers you get Googling seem to be outdated for Lion...

Also note that I have practically zero experience using the Terminal. I'm willing to learn, but please explain for a novice...


Solution 1:

First, one thing to recognize about OS X is that it is built on Unix. This is where the .bash_profile comes in. When you start the Terminal app in OS X you get a bash shell by default. The bash shell comes from Unix and when it loads it runs the .bash_profile script. You can modify this script for your user to change your settings. This file is located at:

~/.bash_profile

Update for Mavericks

OS X Mavericks does not use the environment.plist - at least not for OS X windows applications. You can use the launchd configuration for windowed applications. The .bash_profile is still supported since that is part of the bash shell used in Terminal.

Lion and Mountain Lion Only

OS X windowed applications receive environment variables from the your environment.plist file. This is likely what you mean by the ".plist" file. This file is located at:

~/.MacOSX/environment.plist

If you make a change to your environment.plist file then OS X windows applications, including the Terminal app, will have those environment variables set. Any environment variable you set in your .bash_profile will only affect your bash shells.

Generally I only set variables in my .bash_profile file and don't change the .plist file (or launchd file on Mavericks). Most OS X windowed applications don't need any custom environment. Only when an application actually needs a specific environment variable do I change the environment.plist (or launchd file on Mavericks).

It sounds like what you want is to change the environment.plist file, rather than the .bash_profile.

One last thing, if you look for those files, I think you will not find them. If I recall correctly, they were not on my initial install of Lion.

Edit: Here are some instructions for creating a plist file.

  1. Open Xcode
  2. Select File -> New -> New File...
  3. Under Mac OS X select Resources
  4. Choose a plist file
  5. Follow the rest of the prompts

To edit the file, you can Control-click to get a menu and select Add Row. You then can add a key value pair. For environment variables, the key is the environment variable name and the value is the actual value for that environment variable.

Once the plist file is created you can open it with Xcode to modify it anytime you wish.

Solution 2:

Your .profile or .bash_profile are simply files that are present in your "home" folder. If you open a Finder window and click your account name in the Favorites pane, you won't see them. If you open a Terminal window and type ls to list files you still won't see them. However, you can find them by using ls -a in the terminal. Or if you open your favorite text editor (say TextEdit since it comes with OS X) and do File->Open and then press Command+Shift+. and click on your account name (home folder) you will see them as well. If you do not see them, then you can create one in your favorite text editor.

Now, adding environment variables is relatively straightforward and remarkably similar to windows conceptually. In your .profile just add, one per line, the variable name and its value as follows:

export JAVA_HOME=/Library/Java/Home
export JRE_HOME=/Library/Java/Home

etc.

If you are modifying your "PATH" variable, be sure to include the system's default PATH that was already set for you:

export PATH=$PATH:/path/to/my/stuff

Now here is the quirky part, you can either open a new Terminal window to have the new variables take effect, or you will need to type .profile or .bash_profile to reload the file and have the contents be applied to your current Terminal's environment.

You can check that your changes took effect using the "set" command in your Terminal. Just type set (or set | more if you prefer a paginated list) and be sure what you added to the file is there.

As for adding environment variables to GUI apps, that is normally not necessary and I'd like to hear more about what you are specifically trying to do to better give you an answer for it.

Solution 3:

Here's a bit more information specifically regarding the PATH variable in Lion OS 10.7.x:

If you need to set the PATH globally, the PATH is built by the system in the following order:

  1. Parsing the contents of the file /private/etc/paths, one path per line
  2. Parsing the contents of the folder /private/etc/paths.d. Each file in that folder can contain multiple paths, one path per line. Load order is determined by the file name first, and then the order of the lines in the file.
  3. A setenv PATH statement in /private/etc/launchd.conf, which will append that path to the path already built in #1 and #2 (you must not use $PATH to reference the PATH variable that has been built so far). But, setting the PATH here is completely unnecessary given the other two options, although this is the place where other global environment variables can be set for all users.

These paths and variables are inherited by all users and applications, so they are truly global -- logging out and in will not reset these paths -- they're built for the system and are created before any user is given the opportunity to login, so changes to these require a system restart to take effect.

BTW, a clean install of OS 10.7.x Lion doesn't have an environment.plist that I can find, so it may work but may also be deprecated.