You see, any directory in your users’s PATH is global. That means you can issue a command by simply entering the command – you do not have to enter the full path to the command. That is why you don’t always have to enter /usr/bin/ls and you can just enter ls.

In this article, we step back for a bit of Linux basics and learn how to add directories to your path.

See what’s already there

If you are curious to know what is already in your PATH you can do so by entering the command echo $PATH. You should see something like:

/usr/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games

The above is pretty standard for a default Linux path. What you are seeing is global paths, each separated by a “:”. Any file in:

• /usr/bin
• /usr/local/sbin
• /usr/local/bin
• /usr/sbin
• /usr/bin
• /sbin
• /usr/games

will be global for the user.

Adding a new directory

There are three ways to add a new directory to your path. Let’s take a look at them individually. The first method only adds the new directory to the PATH temporarily. This is great for testing purposes, but know that the minute you log out that directory is removed from the users’ path.

Let’s say you have the directory ~/scripts that you want to add temporarily. To do this open up a terminal window and issue the command:

PATH=$PATH:/home/USERNAME/scripts

Where USERNAME is the actual name of the user you are using. Now if you issue the command echo $PATH that new directory will be listed. Log out and log in and issue that same command and the directory will be gone.

Now let’s say you want to make that addition permanent for the user. This was typically done in the users’ ~/.bash_profile file. You might notice that you don’t have such a file. Newer Ubuntu releases have opted for the ~/.profile file instead. I still prefer to create a ~/.bash_profile for these purposes.  So if you don’t have a ~/.bash_profile create one and open it. If you have a ~/.bash_profile open it. and add a line like:

PATH=”$HOME/bin:$PATH:/home/USER/scripts:”

Where USER is the actual user name.

You might think you would have to log out and log back in. You don’t. Just issue the command source .bash_profile and the changes will take effect.

You can also add this path to every users PATH by adding the same line to the /etc/profile. You probably won’t find a reference to PATH in that file. So what you have to do is add the following lines to the end of that file:
PATH=$PATH:/home/USER/scripts
export PATH
Where USER is the actual user name. Of course you probably don’t want to add a directory of one user to everyone’s PATH, so you might want to create a new directory (like /data/scripts) and add that the to /etc/profile. Once you are done save that and the next time someone logs in they will have that new directory in their PATH.

Final thoughts

Linux is all about flexibility. As you can see it is possible to really stretch the usability of your directory structure to make it work for you instead of against you. Adding directories to your PATH variable allows you to create scripts that can be run globally, and by anyone.

I did this by moving the profile to my encrypted hard drive. The hard drive is encrypted using True Crypt and the profile can only be accessed if I provide the security key to decrypt the hard drive. Other means are theoretically possible as well, use a portable device that has to be plugged in before you can use the profile.

Moving a profile to another location is not difficulty at all. Close all instances of Firefox and locate your profile folder. This is usually in Document and Settings under Application Date, Mozilla, Firefox, Profiles of the user who is logged into windows currently.

Move the complete folder to a different location. Open up profiles.ini afterwards (located in Firefox in Document and Settings). Change the path= parameter to the new location of your profile and change the parameter IsRelative=1 to 0.

Restart Firefox to see if the changes have been made. If all your bookmarks for instance load fine the changes have been successful. If that is not the case double-check the path parameter in profiles.ini.