Revisions to Setting PATH variable in /etc/environment vs .profile

further info on how user's local bin directories are added to PATH on 18.04

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edit approved Nov 1, 2019 at 19:46

AlbertB

33
4

The /etc/environment file normally contains only this line:
```
 PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games" 
```
It sets the PATH variable for all users on the system to this default value, which should not be changed in a major way. At least you should not remove any of the important paths like /bin, /sbin, /usr/bin and /usr/sbin from it.

This file is read as one of the first configuration files by every shell of every user. Note that it is not a shell script. It is just a configuration file that gets parsed somehow and that may only contain environment variable assignments!
The ~/.profile file can contain many things, by default it contains amongst other stuff a check whether a ~/bin directory exists and adds that to the user's existing PATH variable, like this (on older Ubuntu releases prior to 16.04 - newer releases add- which adds it unconditionally -- and on 18.04, which also adds "~/.local/bin"):
```
 # set PATH so it includes user's private bin if it exists if [ -d "$HOME/bin" ] ; then PATH="$HOME/bin:$PATH" fi 
```
You see that the old value of PATH gets reused here and the new path is only appended to the beginning instead of overwriting everything. When you manually want to add new paths, you should also always keep the old $PATH value somewhere in the new string.

This initialization script is read only by the shells of the user to which it belongs, but there's another condition:
```
 # ~/.profile: executed by the command interpreter for login shells. # This file is not read by bash(1), if ~/.bash_profile or ~/.bash_login # exists. 
```
So if you use the default Bash shell, you should make sure that you don't have a ~/.bash_profile or ~/.bash_login if you want the changes in ~/.profile to have an effect for your user.

The /etc/environment file normally contains only this line:
```
 PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games" 
```
It sets the PATH variable for all users on the system to this default value, which should not be changed in a major way. At least you should not remove any of the important paths like /bin, /sbin, /usr/bin and /usr/sbin from it.

This file is read as one of the first configuration files by every shell of every user. Note that it is not a shell script. It is just a configuration file that gets parsed somehow and that may only contain environment variable assignments!
The ~/.profile file can contain many things, by default it contains amongst other stuff a check whether a ~/bin directory exists and adds that to the user's existing PATH variable, like this (on older Ubuntu releases prior to 16.04 - newer releases add it unconditionally):
```
 # set PATH so it includes user's private bin if it exists if [ -d "$HOME/bin" ] ; then PATH="$HOME/bin:$PATH" fi 
```
You see that the old value of PATH gets reused here and the new path is only appended to the beginning instead of overwriting everything. When you manually want to add new paths, you should also always keep the old $PATH value somewhere in the new string.

This initialization script is read only by the shells of the user to which it belongs, but there's another condition:
```
 # ~/.profile: executed by the command interpreter for login shells. # This file is not read by bash(1), if ~/.bash_profile or ~/.bash_login # exists. 
```
So if you use the default Bash shell, you should make sure that you don't have a ~/.bash_profile or ~/.bash_login if you want the changes in ~/.profile to have an effect for your user.

The /etc/environment file normally contains only this line:
```
 PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games" 
```
It sets the PATH variable for all users on the system to this default value, which should not be changed in a major way. At least you should not remove any of the important paths like /bin, /sbin, /usr/bin and /usr/sbin from it.

This file is read as one of the first configuration files by every shell of every user. Note that it is not a shell script. It is just a configuration file that gets parsed somehow and that may only contain environment variable assignments!
The ~/.profile file can contain many things, by default it contains amongst other stuff a check whether a ~/bin directory exists and adds that to the user's existing PATH variable, like this (on older Ubuntu releases prior to 16.04 -- which adds it unconditionally -- and on 18.04, which also adds "~/.local/bin"):
```
 # set PATH so it includes user's private bin if it exists if [ -d "$HOME/bin" ] ; then PATH="$HOME/bin:$PATH" fi 
```
You see that the old value of PATH gets reused here and the new path is only appended to the beginning instead of overwriting everything. When you manually want to add new paths, you should also always keep the old $PATH value somewhere in the new string.

This initialization script is read only by the shells of the user to which it belongs, but there's another condition:
```
 # ~/.profile: executed by the command interpreter for login shells. # This file is not read by bash(1), if ~/.bash_profile or ~/.bash_login # exists. 
```
So if you use the default Bash shell, you should make sure that you don't have a ~/.bash_profile or ~/.bash_login if you want the changes in ~/.profile to have an effect for your user.