The /etc/environment file is not executing certain commands - bash

Given below are the contents of my /etc/environment file
alias ...="cd ../../"
alias ls="ls -al"
export blah="blah blah"
When I start new terminal session and change to sudo user as sudo su, only the export command has run, which I am able to verify using env. The aliases are not set.
If I run source /etc/environment the aliases get set as expected. Am I missing something? I also read that /etc/environment is only read when the system boots. Is that true?
I am running on RHEL 7.

The /etc/environment is intended for setting environment variables for every user on login. Therefore you don't need to use export in this file.
Adding alias into this file won't work, because this file is not a shell script and only accepts variable=value pairs.
/etc/environment is used by the PAM-env module and is agnostic to
login/non-login, interactive/non-interactive and also Bash/non-Bash,
so scripting or glob expansion cannot be used. The file only accepts
variable=value pairs.
It's not possible to export aliases or set them globally - they need to be set again in every shell instance.
The file you want to use is ~/.bashrc in a home directory of a user. This file gets executed every time a user opens a bash shell. So aliases and variables set in this file will have effect only on that shell.
You can also use /etc/bash.bashrc which is System-wide .bashrc file for interactive bash shells.
The reason why the export in your /etc/environment worked and actually created and env variable is that the pam-env parser specifically ignores export keyword to avoid confusion for people who don't know that /etc/environment is not a shell script.
You can see that in pam_env.c source code
/* skip over "export " if present so we can be compat with
bash type declarations */
if (strncmp(key, "export ", (size_t) 7) == 0)
key += 7;
Its available for example here - Linux-PAM/pam_env.c v0.79. See line 00234.

Related

Set global Environment variable on Mac OS Mojave

I've searched for an answer and read about different ways to do that in Mac but some of them are not relevant for Mojave or just didn't work for me.
I need to set Environment variable in terminal (bash), run script that creates processes, and I would like those processes to know the value of those environment variables.
How can I do that?
btw - writing export ENV_NAME=ENV_VAL in .bashrc or in .bash_profile didn't work.
Works for me. Have you RTFM? For example, ~/.bashrc is only read by interactive shells, not shell scripts. And ~/.bash_profile is only read by login shells. Again, shell scripts don't usually use the -l flag that would make them login shells. Also, if you put an export VAR=value statement in your ~/.bashrc it won't affect your current interactive shell. You need to start a new shell; e.g., by typing exec bash. Once you do that you should find the env var is defined. And it will be inherited by any process, including a shell script, you launch from that interactive session.
Note that if you run your script via crontab, for example, then you'll need a different means of setting the env var. For example, by using the --init-file flag or the BASH_ENV env var.

Correctly formatting a PYTHONPATH in my .bash_profile

I would like to add a PYTHONPATH to my .bash_profile but would like to check I'm doing this the correct way. My .bash_profile (without a PYTHONPATH) looks like:
# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi
# User specific environment and startup programs
PATH=$PATH:$HOME/.local/bin:$HOME/bin:/home/user/condor/bin:/home/user/merlin/bin
export PATH
The path I would like to add to my PYTHONPATH is:
/home/user/merlin/bin/strats/
Therefore would my updated .bash_profile (with PYTHONPATH) looks like:
# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi
# User specific environment and startup programs
PATH=$PATH:$HOME/.local/bin:$HOME/bin:/home/user/condor/bin:/home/user/merlin/bin
export PATH
export PYTHONPATH=/home/user/merlin/bin/strats/
How can I correctly format this?
If it's your wish to be the sole owner and decision maker regarding PYTHONPTAH environment variable content on your interactive login shells, you're doing it right:
~/.bash_profile or ~/.profile
export PYTHONPATH=/home/user/merlin/bin/strats/
If you'd like to inherit any system-wide setting for PYTHONPATH environment variable, then you should:
~/.bash_profile or ~/.profile
export PYTHONPATH=$PYTHONPATH:/home/user/merlin/bin/strats/
Be aware that if you're working in a system where you can launch new terminals without logging in (i.e: launching a new xterm on your linux desktop), or in case you need that specific environment variable to run a script via cron, .bash_profile won't be executed and therefore the environment variable won't be available to that script.
As discussed in this answer comments, you can choose to use the ./~profile file instead of ~/.bash_profile to have additional compatibility with other shells.
Some folks simply add all environment configuration in ~/.bashrc. Since your .bash_profile template call ~/.bashrc, you'd end up having those environment variables available in interactive login and non-login shells.
For scripts that run via cron, you should directly source the file where you have your environment configuration on the script itself or on the cron line because that won't be done automatically for you (crontab launches non-interactive shells to run the scripts and these are not affected by ~/.bashrc, ~/.bash_profile or ~/.profile).

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On Linux, how can I add a directory to the $PATH so it remains persistent across different sessions?
Background
I'm trying to add a directory to my path so it will always be in my Linux path. I've tried:
export PATH=$PATH:/path/to/dir
This works, however each time I exit the terminal and start a new terminal instance, this path is lost, and I need to run the export command again.
How can I do it so this will be set permanently?
You need to add it to your ~/.profile or ~/.bashrc file.
export PATH="$PATH:/path/to/dir"
Depending on what you're doing, you also may want to symlink to binaries:
cd /usr/bin
sudo ln -s /path/to/binary binary-name
Note that this will not automatically update your path for the remainder of the session. To do this, you should run:
source ~/.profile
or
source ~/.bashrc
There are multiple ways to do it. The actual solution depends on the purpose.
The variable values are usually stored in either a list of assignments or a shell script that is run at the start of the system or user session. In case of the shell script you must use a specific shell syntax and export or set commands.
System wide
/etc/environment List of unique assignments. Allows references. Perfect for adding system-wide directories like /usr/local/something/bin to PATH variable or defining JAVA_HOME. Used by PAM and systemd.
/etc/environment.d/*.conf List of unique assignments. Allows references. Perfect for adding system-wide directories like /usr/local/something/bin to PATH variable or defining JAVA_HOME. The configuration can be split into multiple files, usually one per each tool (Java, Go, and Node.js). Used by systemd that by design do not pass those values to user login shells.
/etc/xprofile Shell script executed while starting X Window System session. This is run for every user that logs into X Window System. It is a good choice for PATH entries that are valid for every user like /usr/local/something/bin. The file is included by other script so use POSIX shell syntax not the syntax of your user shell.
/etc/profile and /etc/profile.d/* Shell script. This is a good choice for shell-only systems. Those files are read only by shells in login mode.
/etc/<shell>.<shell>rc. Shell script. This is a poor choice because it is single shell specific. Used in non-login mode.
User session
~/.pam_environment. List of unique assignments, no references allowed. Loaded by PAM at the start of every user session irrelevant if it is an X Window System session or shell. You cannot reference other variables including HOME or PATH so it has limited use. Used by PAM.
~/.xprofile Shell script. This is executed when the user logs into X Window System system. The variables defined here are visible to every X application. Perfect choice for extending PATH with values such as ~/bin or ~/go/bin or defining user specific GOPATH or NPM_HOME. The file is included by other script so use POSIX shell syntax not the syntax of your user shell. Your graphical text editor or IDE started by shortcut will see those values.
~/.profile, ~/.<shell>_profile, ~/.<shell>_login Shell script. It will be visible only for programs started from terminal or terminal emulator. It is a good choice for shell-only systems. Used by shells in login mode.
~/.<shell>rc. Shell script. This is a poor choice because it is single shell specific. Used by shells in non-login mode.
Notes
GNOME on Wayland starts a user login shell to get the environment. It effectively uses the login shell configurations ~/.profile, ~/.<shell>_profile, ~/.<shell>_login files.
Man pages
environment
environment.d https://linux.die.net/man/1/environment.d
bash
dash
Distribution-specific documentation
Ubuntu
Arch Linux
Related
Difference between Login Shell and Non-Login Shell?
In Ubuntu, edit /etc/environment. Its sole purpose is to store environment variables. Originally the $PATH variable is defined here.
This is a paste from my /etc/environment file:
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games"
So you can just open up this file as root and add whatever you want.
For immediate results,
Run (try as normal user and root):
source /etc/environment && export PATH
If you use Z shell (zsh), add this line right after the comments in /etc/zsh/zshenv file:
source /etc/environment
I encountered this little quirk on Ubuntu 15.10 (Wily Werewolf), but if your zsh is not getting the correct PATH, this could be why.
For Bash, you can put the export declaration in ~/.bashrc. For example, my .bashrc contains this line:
export PATH=/var/lib/gems/1.8/bin:/home/ash/.bin:$PATH
You may set $PATH permanently in two ways.
To set the path for a particular user:
You may need to make the entry in file .bash_profile in the home directory for the user.
E.g, in my case I will set the java path in the Tomcat user profile*
echo "export PATH=$PATH:/path/to/dir" >> /home/tomcat/.bash_profile
To set a common path for all system users, you may need to set the path like this:
echo "export PATH=$PATH:/path/to/dir" >> /etc/profile
You can use on CentOS or Red Hat Linux (RHEL) for the local user:
echo $"export PATH=\$PATH:$(pwd)" >> ~/.bash_profile
This adds the current directory (or you can use another directory) to the PATH. This makes it permanent, but it takes effect at the next user logon.
If you don't want do a re-logon, then you can use:
source ~/.bash_profile
That reloads the # User specific environment and startup programs. This comment is present in file .bash_profile.
You can also set it permanently, editing one of these files:
/etc/profile (for all users)
~/.bash_profile (for current user)
~/.bash_login (for current user)
~/.profile (for current user)
You can also use /etc/environment to set a permanent PATH environment variable, but it does not support variable expansion.
Extracted from: Linux: Añadir ruta al PATH
I think the most elegant way is:
Add this in the ~/.bashrc file.
Run this command:
gedit ~/.bashrc
Add your path inside it:
export PATH=$PATH:/opt/node/bin
source ~/.bashrc
(Ubuntu)
Modify the "/etc/profile" file:
vi /etc/profile
Press the I key to enter editing mode and move the cursor to the end of the file. Additional entries:
export PATH=$PATH:/path/to/dir;
Press the Esc key to exit edit mode, and :wq to save the file.
Make the configuration effective
source /etc/profile
Explanation:
The profile file works for all users. If you want it to be valid only for the active user, change the ".bashrc" file.
I stumbled across this question yesterday when searching for a way to add a folder containing my own scripts to the PATH - and was surprised to find out that my own ~/.profile file (on Linux Mint 18.1) already contained this:
# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/bin" ] ; then
PATH="$HOME/bin:$PATH"
fi
Thus, all I had to do was create the folder ~/bin and put my scripts there.
You can add that line to your console configuration files (e.g., .bashrc, or to .profile).
After so much research, I found a simple solution for this (I am using Elementary OS), inspired by Flutter – Step by Step Installation on Linux – Ubuntu.
Run the following command to open the .bashrc file in edit mode. (You
may also use vi or any other editor).
~$ sudo nano ~/.bashrc
Add the following line at the end of the file and save.
export PATH="[FLUTTER_SDK_PATH]/flutter/bin:$PATH"
For example:
export PATH="/home/rageshl/dev/flutter/bin:$PATH"
I believe this is the permanent solution for setting the path in Flutter in a Ubuntu distribution.
It can be directly added by using the following command:
echo 'export PATH=$PATH:/new/directory' >> ~/.zshrc
source ~/.zshrc
One way to add a permanent path, which worked for me, is:
cd /etc/profile.d
touch custom.sh
vi custom.sh
export PATH=$PATH:/path according to your setting/
Restart your computer and here we go; the path will be there permanently.
Add script file [name_of_script].sh to the /etc/profile.d folder with the line:
export PATH=$PATH:/dir
Every script within the /etc/profile.d folder is automatically executed by /etc/profile on login.
My answer is in reference to the setting up of a Go environment on Ubuntu Linux (amd64). I have faced the same trouble of setting the path of environment variables (GOPATH and GOBIN), losing it on terminal exit and rebuilding it using the source <file_name> every time.
The mistake was to put the path (GOPATH and GOBIN) in ~/.bash_profile file. After wasting a few good hours, I found that the solution was to put GOPATH and GOBIN in the ~/.bash_rc file in the manner:
export GOPATH=$HOME/go
export GOBIN=$GOPATH/bin
export PATH=$PATH:$GOPATH:$GOBIN
And in doing so, the Go installation worked fine and there were no path losses.
The reason with which this issue can be related is that settings for non-login shells, like your Ubuntu terminal or GNOME terminal where we run the Go code, are taken from the ~./bash_rc file and the settings for login shells are taken from ~/.bash_profile file. And from the ~/.profile file if the ~/.bash_profile file is unreachable.
The files where you add the export command depends on if you are in login-mode or non-login-mode.
If you are in login-mode, the files you are looking for are either /etc/bash or /etc/bash.bashrc.
If you are in non-login-mode, you are looking for the file /.profile or for the files within the directory /.profiles.d
The files mentioned above is where the system variables are.
Permanently add to the PATH variable
Global:
echo "export PATH=$PATH:/new/path/variable" >> /etc/profile
Local (for the current user only):
echo "export PATH=$PATH:/new/path/variable" >> ~/.profile
For global, restart. For local, relogin.
Example
Before:
$ cat /etc/profile
#!/bin/sh
export PATH=/usr/bin:/usr/sbin:/bin:/sbin
After:
$ cat /etc/profile
#!/bin/sh
export PATH=/usr/bin:/usr/sbin:/bin:/sbin
export PATH=/usr/bin:/usr/sbin:/bin:/sbin:/new/path/variable
Alternatively you can just edit file "profile":
$ cat /etc/profile
#!/bin/sh
export PATH=/usr/bin:/usr/sbin:/bin:/sbin:/new/path/variable
Another way (thanks gniourf_gniourf):
echo 'PATH=$PATH:/new/path/variable' >> /etc/profile
You shouldn't use double quotes here! echo 'export
PATH=$PATH:/new/path/variable'... And by the way, the export keyword
is very likely useless as the PATH variable is very likely already
marked as exported. – gniourf_gniourf
Zues77 has the right idea. The OP didn't say "How can I hack my way through this?". The OP wanted to know how to permanently append to $PATH:
sudo nano /etc/profile
This is where it is set for everything and is the best place to change it for all things needing $PATH.
Let's say you're running macOS. You have a binary you trust and would like to make available across your system, but don't necessarily want the directory in which the binary is to be added to your PATH.
You can opt to copy/move the binary to /usr/local/bin, which should already be in your PATH. This will make the binary executable like any other binary you may already have access to in your terminal.
The simplest way is the following line,
PATH="<directory you want to include>:$PATH"
in your .bashrc file in the home directory.
It will not get reset even if you close the terminal or reboot your PC. It's permanent.
This is a one-liner. It adds a line to the .bashrc. That line is going to check if the directory has already been added to the path and append if not. This will prevent duplicating your directory in the path every time you source .bashrc.
echo "[[ \":\$PATH:\" != *\":$(pwd)/path/to/add:\"* ]] && export PATH=\"\${PATH:+\${PATH}}:$(pwd)/path/to/add\"" >> ~/.bashrc
source ~/.bashrc
I think the most elegant way is:
Add this in the ~./bashrc file:
if [ -d "new-path" ]; then
PATH=$PATH:new-path
fi
source *~/.bashrc*
(Ubuntu)
For a Debian distribution, you have to:
edit file ~/.bashrc. E.g: vim ~/.bashrc
add export PATH=$PATH:/path/to/dir
then restart your computer. Be aware that if you edit file ~/.bashrc as root, your environment variable you added will work only for root

Cygwin shell doesn't execute .bashrc

After start the cygwin shell, it just locate in a wrong home dir:
xfire#codingme.com ~
$ pwd
/cygdrive/c/Users/xfire
But it used to be /home/xfire
xfire#codingme.com /etc
$ cat passwd | grep xfire
xfire:unused:22773:10513:U-CORP\xfire,S-1-5-21-527237240-725345543-682003330-12773:/home/xfire:/bin/bash
And the .bashrc in the /home/xfire was not executed, even I copy it to the /cygdrive/c/Users/xfire, it also doesn't work!
On cygwin, I add this to my ~/.bash_profile:
. ~/.bashrc
Some program add an "HOME" environment in windows registry and set the value to "C:\Users\xfire", that's why cygwin take that directory as the home. cygwin.com/faq-nochunks.html
On my version of cygwin I found that only ~/.profile was being execueted so added
if [ -e "${HOME}/.bash_profile" ]; then
source "${HOME}/.bash_profile"
fi
to the .profile file. My .bash_profile file contains another test for .bashrc and executes that from inside there. I also added the following two lines to my .bashrc file.
export BASH_ENV="${HOME}/.profile"
export ENV="${HOME}/.profile"
The first of these ensures that .profile gets executed in non-interactive terminals and the second ensures it gets executed in POSIX terminals. I found a very useful explanation of what get run and when in the Bash Reference Manual.
In your case it wouldn't help as you have an issue with the value of your HOME environment variable but this page comes up quite high on the list when searching for this issue.
You can also also set BASH_ENV variable, e.g., BASH_ENV='C:\DOCUME~1\dwyttenb\.bashrc'
~/.bash_profile is executed before the initial command prompt is returned to the user. After that, every time a new shell is opened, ~/.bashrc is executed.
Adding . ~/.bashrc at end of ~/.bash_profile has resolved the problem.
Now you can check existing aliases using alias command.
Find more details on github.

Hiding the text before an input to only $-sign in Bash?

I have this in .bashrc;
PS1='$'
However, I see this still in terminal:
mas-macbook:some/path mas$
I want
$
PS1 should already have been exported long before you get to your .bashrc file, at least for a login shell. In that case, setting PS1 should simply overwrite the value (not its export status).
One thing to keep in mind is that bash itself does not run your .bashrc file for a login shell. The actual sequence of execution is:
/etc/profile, if there.
first of ~/.bash_profile, ~/.bash_login or ~/.profile.
I'm fairly certain that, if you want .bashrc to run for a login shell, it has to be sourced from one of those above.
For example, /etc/profile may call /etc/profile.local or all the scripts in the /etc/profile.d/ directory. Similarly, my .bash_profile calls the following, if they exist:
/etc/bash.bashrc
~/.bashrc
with the following snippet:
if [ -e /etc/bash.bashrc ] ; then
source /etc/bash.bashrc
fi
if [ -e "${HOME}/.bashrc" ] ; then
source "${HOME}/.bashrc"
fi
When I change PS1 and echo "hello" in my .bashrc, but comment out the sourcing of it in .bash_profile, the prompt doesn't get changed (nor the string printed) when I log in. When I uncomment the sourcing, I get both the string printed and the prompt changed when I log in.
To make sure that your .bashrc is called for your login shells, put that echo hello statement just after setting PS1, then log in to check.
If it is being called when you log in, you can execute "export -p" from your shell to get a list of all the exported variables - make sure PS1 has a "declare -x" in front of it. If not, just change your .bashrc to export it as well:
export PS1='$'
If it's already exported, then something is changing it after your set statement. In that case, you'll need to actually look at the login execution path to see what's getting called before it gives you control.
I think you need the export keyword:
export PS1='$'
You may have to escape the $ symbol. This works in my system...
PS1="\$"
If that don't work, please run the command 'echo $PS1' and let us know the results. You may also have to send the .bashrc file - it possible that you have set the PS1 variable before including the global /etc/bashrc file. If that's the case, the global file will overwrite the variable. You will have to set the PS1 variable after including the /etc/bashrc file.

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