How to reset my $PATH environment variable back to default?

Question

I am a noobie. I tried searching the duplicates for answers, but none worked. I accidentally altered my $PATH variable in my terminal when trying to install ghc. Every time I open a terminal window I get:

bash: export: `/.cabal/bin:/opt/ghc/7.6.3/bin:': not a valid identifier
bash: warning: here-document at line 120 delimited by end-of-file (wanted 
EOF')
Command 'cat' is available in '/bin/cat'
The command could not be located because '/bin' is not included in the 
PATH environment variable.
cat: command not found

When I type:

echo $PATH

it gives me the following:

/.cabal/bin:/opt/cabal/1.16/bin:/opt/ghc/7.6.3/bin:

I can fix it by typing:

source /etc/environment

But that's only for the current terminal session. If I close the window and open a new one, it goes back to the wrong $PATH.

How can I permanently reset my $PATH back to the default?

Answer 1

Building on the comments made by steeldriver try the following two simple steps:

1. Backup existing config:

mv -v ~/.bashrc ~/.bashrc_bak && mv -v ~/.profile  ~/.profile_bak

2. Create new, safe copies:

cp -v /etc/skel/{.bashrc,.profile} $HOME

Note: This can all be accomplished with a one-liner, demonstrated on my own system:

andrew@athens:~$ cp -v -S _bak /etc/skel/{.bashrc,.profile} $HOME
'/etc/skel/.bashrc' -> '/home/andrew/.bashrc' (backup: '/home/andrew/.bashrc_bak')
'/etc/skel/.profile' -> '/home/andrew/.profile' (backup: '/home/andrew/.profile_bak')
andrew@athens:~$ 

And finally add any customisations made by yourself previously from the 2 backup files, by 'customisations' I mean such things as:

1. Alterations to the default $PATH made in these files, I note in your case you have installed to /opt which is not in the default $PATH
2. Alterations to the default Terminal prompt
3. Additions to the default aliases

And any other changes that have been made to the safe defaults of both files...

Answer 2

There are a lot of options. You can give a look here.

Keep in mind that in the link I sent you they mainly suggest how to set the path in the current session.

However if you change the path to the suggested values in ~/.profile or ~/.bashrc (depending which one you modified) you should be fine.

Answer 3

I hope this is helpful:

rick@dell:~$ echo "$PATH"
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin

I haven't changed my path (that I can recall) I notice "games" is in there but I don't play games so I assume it's a default. You might want to use this as a starting path to get you started on the right path, so to speak.

I'm using Ubuntu 16.04.

To add paths this link might be helpful: unix-linux-adding-path.

Answer 4

Follow these step to recover the PATH environment variable :

• Delete the culprit file from /etc/profile.d/ (if any)
• Delete the culprit line from /etc/profile or ~/.bashrc (if any)
• Execute source /etc/environment to start reseting the path environment variable
• Execute source /etc/profile followed by source /etc/profile.d/*
• At last source ~/.bashrc