48

I accidentally unset all the directories of $PATH while trying to add a new one in ~/.bashrc. I opened a new terminal window as I was editing and now $PATH is empty. I'm worried if I boot from another drive to find the $PATH I won't be able to boot into this drive again.

Basically, what is the default result of echo $PATH?

muru
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Cee
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    Comment out or fix that export line and you should e good to go. – Panther Mar 16 '12 at 05:28
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    ~/.bashrc is the wrong place to set environment variables though. You should do that in ~/.profile instead. – geirha Mar 16 '12 at 06:38
  • Yes I figured it out. PATH is still fine in the other terminal window that was open before the new one, so just fixing the export line by adding :$PATH at the end restored the PATH. And yes in ~/.profile there is code to "set PATH so it includes user's private bin if it exists" i.e. $HOME/bin – Cee Mar 16 '12 at 08:24

4 Answers4

51

The answer to your question is:

PATH=$(getconf PATH)

and works on any POSIX compliant system. The selected answer is the correct way to augment the path without obliterating prior existing content. If you use bash, you might consider:

PATH+=:$mynewdir
Zanna
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Bruce
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    I had trouble using a lot of commands (sed: No such file or directory type of trouble) after accidentally setting my PATH to nothing during a very long running process (i.e., I couldn't restart). I couldn't use getconf. To reset my path, I used $(export $(cat /etc/environment)":/usr/bin/additional:/usr/bin/paths"). For the curious: /etc/environment is where the PATH variable is initially set in many Linux flavours. – Nick Bull Aug 18 '15 at 14:28
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    That working would surprise me. Perhaps "export" without the surrounding "$(...)" stuff might, but it will be whatever happens to be there. Use "source /etc/..". Anyway, try "/usr/bin/getconf" if you cannot even find "getconf". – Bruce Aug 31 '15 at 21:56
  • Prefer your final idea using the full path a lot more than mine in hindsight! Thanks for the reply – Nick Bull Sep 01 '15 at 09:05
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    If the PATH variable is empty, then PATH=$(getconf PATH) will not be useful but only result in bash: getconf: No such file or directory – Max N May 31 '18 at 16:20
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    If PATH is empty, then note the comment above: try "/usr/bin/getconf". If that does not work, then you need to learn where your system stashes its POSIX commands and use that directory. – Bruce Jun 01 '18 at 17:06
  • /usr/bin/getconf should be added to the answer itself. This works. – NelsonGon Dec 25 '21 at 22:02
  • Most cleverly, not all systems put POSIX commands in /usr/bin. It is system dependent. SO: 1- get to know your systems, and 2- /usr/bin/getconf works 99% :) – Bruce Mar 27 '22 at 17:51
29

You can find it on /etc/environment:

$ /usr/bin/cat /etc/environment

PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games"

So, just source it: 

$ source /etc/environment 
$ echo $PATH

/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
Manuel Jesus Rodriguez
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11

Adding :$PATH to the end of the export line fixed the problem e.g. export PATH=<directory to be added>:$PATH

I add this line to the ~/.bash_rc file instead of the ~/.profile file so I can see the effect immediately in a new terminal and for other reasons based on the information here: https://superuser.com/questions/176404/linux-bash-not-loading-profile-in-new-session

For me, the default output of echo $PATH before adding the new directory is:

/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
Zanna
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Cee
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4

The default path is 

/home/_username_/bin:/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games

Hope this helps you

Vibhav
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