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Mac OS X: Set / Change $PATH Variable
by VIVEK GITE on AUGUST 25, 2013
I need to add dev tools (such as JDK and friends) to my PATH. How do I change $PATH variable in OS X 10.8.x? Where does $PATH get set in OS X 10.8 Mountain Lion?

Tutorial details
Difficulty Easy (rss)
Root privileges No
Requirements None
Estimated completion time 5m
$PATH is nothing but an environment variable on Linux, OS X, Unix-like operating systems, and Microsoft Windows. You can specify a set of directories where executable programs are located using $PATH. The $PATH variable is specified as a list of directory names separated by colon (:) characters. To print the current settings, open the Terminal and then type:

echo "$PATH"

OR


printf "%s\n" $PATH

Sample outputs:

Fig.01: Displaying the current $PATH settings using echo / printf on OS X
Fig.01: Displaying the current $PATH settings using echo / printf on OS X
OS X: Change your PATH environment variable

You can add path to any one of the following method:

$HOME/.bash_profile file using export syntax.
/etc/paths.d directory.
Method #1: $HOME/.bash_profile file
The syntax is as follows:

export PATH=$PATH:/new/dir/location1
export PATH=$PATH:/new/dir1:/dir2:/dir/path/no3
In this example, add /usr/local/sbin/modemZapp/ directory to $PATH variable. Edit the file $HOME/.bash_profile, enter:
vi $HOME/.bash_profile

OR
vi ~/.bash_profile

Append the following export command:

export PATH=$PATH:/usr/local/sbin/modemZapp
Save and close the file. To apply changes immedialty enter:
source $HOME/.bash_profile

OR
. $HOME/.bash_profile

Finally, verify your new path settings, enter:
echo $PATH

Sample outputs:

/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/opt/X11/bin:/usr/local/sbin/modemZapp
Method #2: /etc/paths.d directory
Apple recommends the path_helper tool to generate the PATH variable i.e. helper for constructing PATH environment variable. From the man page:

The path_helper utility reads the contents of the files in the directories /etc/paths.d and /etc/manpaths.d and appends their contents to the PATH and MANPATH environment variables respectively.

(The MANPATH environment variable will not be modified unless it is already set in the environment.)

Files in these directories should contain one path element per line.

Prior to reading these directories, default PATH and MANPATH values are obtained from the files /etc/paths and /etc/manpaths respectively.

To list existing path, enter:
ls -l /etc/paths.d/

Sample outputs:

total 16
-rw-r--r-- 1 root wheel 13 Sep 28 2012 40-XQuartz
You can use the cat command to see path settings in 40-XQuartz:
cat /etc/paths.d/40-XQuartz

Sample outputs:

/opt/X11/bin
To set /usr/local/sbin/modemZapp to $PATH, enter:


sudo -s 'echo "/usr/local/sbin/modemZapp" > /etc/paths.d/zmodemapp'

OR use vi text editor as follows to create /etc/paths.d/zmodemapp file:
sudo vi /etc/paths.d/zmodemapp

and append the following text:

/usr/local/sbin/modemZapp
Save and close the file. You need to reboot the system. Alternatively, you can close and reopen the Terminal app to see new $PATH changes.

Conclusion

Use $HOME/.bash_profile file when you need to generate the PATH variable for a single user account.
Use /etc/paths.d/ directory via the path_helper tool to generate the PATH variable for all user accounts on the system. This method only works on OS X Leopard and higher.
See also:
Customize the bash shell environments from the Linux shell scripting wiki.
UNIX: Set Environment Variable
Man pages - bash(1), path_helper(8)