Linux export all variables

How to export variables that are set, all at once?

set command displays all the local variables like below. How do I export these variables all at once?

>set a=123 b="asd asd" c="hello world" 

what do you mean export all at once? you can use semi colons to define in one line. like a=123;b=»asd asd»;c=»hello world»

Your question is unclear. Is that an excerpt of set output you’re showing? If so, then it’s not bash ‘s. Do you want to export all the currently set variable including the special shell variables? Or only those 3 variables like in export a b c ?

export $ would export any defined parameter whose name starts with T . Unfortunately, there doesn’t seem to be a way to easily generate a list of all defined parameters.

5 Answers 5

Run the following command, before setting the variables:

set -a set -o allexport # self-documenting version 

To turn this option off, run set +a or set +o allexport afterwards.

set -a # or: set -o allexport . ./environment set +a 

Where environment contains:

FOO=BAR BAS='quote when using spaces, (, >, $, ; etc' 

This must be enabled before assigning to variables, though. It doesn’t do anything to previously assigned variables.

Same preliminary requirement as chosen answer . either explicitly export each variable as per

or prior to any variable assignment issue

set -a # for details see answer by @nitin 

then this works if your shell is bash ( possibly other shells as well )

your new file will contain a dump of all currently defined variables . with entries like

declare -x PORT="9000" declare -x PORT_ADMIN="3001" declare -x PORT_DOCKER_REGISTRY="5000" declare -x PORT_ENDUSER="3000" declare -x PRE_BUILD_DIR="/cryptdata6/var/log/tmp/khufu01/loud_deploy/curr/loud-build/hygge" declare -x PROJECT_ID="hygge" declare -x PROJECT_ID_BUSHIDO="bushido" 

then to jack up current shell with all those env vars issue

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How to Set Environment Variables in Linux

In this tutorial, you will learn how to set environment variables in Ubuntu, CentOS, Red Hat, basically any Linux distribution for a single user and globally for all users. You will also learn how to list all environment variables and how to unset (clear) existing environment variables.

Environment variables are commonly used within the Bash shell. It is also a common means of configuring services and handling web application secrets.

It is not uncommon for environment specific information, such as endpoints and passwords, for example, to be stored as environment variables on a server. They are also used to set the important directory locations for many popular packages, such as JAVA_HOME for Java.

Setting an Environment Variable

To set an environment variable the export command is used. We give the variable a name, which is what is used to access it in shell scripts and configurations and then a value to hold whatever data is needed in the variable.

For example, to set the environment variable for the home directory of a manual OpenJDK 11 installation, we would use something similar to the following.

export JAVA_HOME=/opt/openjdk11

To output the value of the environment variable from the shell, we use the echo command and prepend the variable’s name with a dollar ($) sign.

And so long as the variable has a value it will be echoed out. If no value is set then an empty line will be displayed instead.

Unsetting an Environment Variable

To unset an environment variable, which removes its existence all together, we use the unset command. Simply replace the environment variable with an empty string will not remove it, and in most cases will likely cause problems with scripts or application expecting a valid value.

To following syntax is used to unset an environment variable

For example, to unset the JAVA_HOME environment variable, we would use the following command.

Listing All Set Environment Variables

To list all environment variables, we simply use the set command without any arguments.

An example of the output would look something similar to the following, which has been truncated for brevity.

BASH=/bin/bash BASHOPTS=checkwinsize:cmdhist:complete_fullquote:expand_aliases:extglob:extquote:force_fignore:globasciiranges:histappend:interactive_comments:login_shell:progcomp:promptvars:sourcepath BASH_ALIASES=() BASH_ARGC=([0]="0") BASH_ARGV=() BASH_CMDS=() BASH_COMPLETION_VERSINFO=([0]="2" [1]="8") BASH_LINENO=() BASH_SOURCE=() BASH_VERSINFO=([0]="5" [1]="0" [2]="3" [3]="1" [4]="release" [5]="x86_64-pc-linux-gnu") BASH_VERSION='5.0.3(1)-release' COLUMNS=208 DIRSTACK=() EUID=1000 GROUPS=() HISTCONTROL=ignoreboth HISTFILE=/home/ubuntu/.bash_history HISTFILESIZE=2000 HISTSIZE=1000 HOME=/home/ubuntu HOSTNAME=ubuntu1904 HOSTTYPE=x86_64 IFS=$' \t\n' LANG=en_US.UTF-8 LESSCLOSE='/usr/bin/lesspipe %s %s' LESSOPEN='| /usr/bin/lesspipe %s' LINES=54

Persisting Environment Variables for a User

When an environment variable is set from the shell using the export command, its existence ends when the user’s sessions ends. This is problematic when we need the variable to persist across sessions.

To make an environment persistent for a user’s environment, we export the variable from the user’s profile script.

Open the current user’s profile into a text editor

export JAVA_HOME=/opt/openjdk11

Adding the environment variable to a user’s bash profile alone will not export it automatically. However, the variable will be exported the next time the user logs in.

To immediately apply all changes to bash_profile, use the source command.

Export Environment Variable

Export is a built-in shell command for Bash that is used to export an environment variable to allow new child processes to inherit it.

To export a environment variable you run the export command while setting the variable.

export MYVAR="my variable value"

We can view a complete list of exported environment variables by running the export command without any arguments.

SHELL=/bin/zsh SHLVL=1 SSH_AUTH_SOCK=/private/tmp/com.apple.launchd.1pB5Pry8Id/Listeners TERM=xterm-256color TERM_PROGRAM=vscode TERM_PROGRAM_VERSION=1.48.2

To view all exported variables in the current shell you use the -p flag with export.

Setting Permanent Global Environment Variables for All Users

A permanent environment variable that persists after a reboot can be created by adding it to the default profile. This profile is loaded by all users on the system, including service accounts.

All global profile settings are stored under /etc/profile. And while this file can be edited directory, it is actually recommended to store global environment variables in a directory named /etc/profile.d, where you will find a list of files that are used to set environment variables for the entire system.

Create a new file under /etc/profile.d to store the global environment variable(s). The name of the should be contextual so others may understand its purpose. For demonstrations, we will create a permanent environment variable for HTTP_PROXY.

sudo touch /etc/profile.d/http_proxy.sh

sudo vi /etc/profile.d/http_proxy.sh

export HTTP_PROXY=http://my.proxy:8080

export HTTPS_PROXY=https://my.proxy:8080

export NO_PROXY=localhost. 1,.example.com

Conclusion

This tutorial covered how to set and unset environment variables for all Linux distributions, from Debian to Red Hat. You also learned how to set environment variables for a single user, as well as all users.

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Linux export Command with Examples

The export command is a built-in Bash shell command that exports environmental variables as child processes without affecting the existing environment variables. Local shell variables are known only to the shell that created them, and starting a new shell session means that previously created variables are unknown to it.

Use the export command to export the variables from a shell, making them global and available in each new shell session.

In this tutorial, you will learn to use the export command and see useful command examples.

Linux export Syntax

The syntax for the export command is:

Running the command without any options outputs all the exported variables and functions:

Exit Status

The command runs successfully unless you pass an invalid option or an invalid variable [name] .

Linux export Options

The options allow users to remove, add, or see previously exported variables. The following table shows the available export options:

Option	Description
-f	Exports [name] s as functions.
-n	Allows users to remove [name] s from the list of exported variables.
-p	Displays a list of all exported variables and functions in the current shell.

1. Using the -p option:

The -p option lists all variable names used in the current shell. Run:

The output lists all the variables used in the current shell session, and it is usually the same as running export without options.

2. Using the -f option:

The -f option exports the variable names as functions. To export a name as a function, create a function in the command line with a unique name. After exporting it, call the function using its name in the command line.

Follow the steps below to create and export a function:

1. Create and call the function by running:

function print_msg < echo "Hello world" >print_msg 

2. Export the function using the -f option:

3. Start a new child shell session and call the function name:

The function works even after starting a child shell as it was previously exported.

3. Using the -n option:

The -n option removes the specified variables and functions from the list of exported variables. In the following example, we remove the EDITOR variable:

Using the grep command to search for the EDITOR variable in the export output prints no results as the variable has been removed:

Linux export Command Examples

The following section showcases useful examples of using the export command.

Assign a Value Before Exporting

Assign a value to a variable before exporting it using the export command. For example:

After setting the value, export the variable:

Print the value of the variable using the echo command or printenv :

Export Multiple Variables

Export multiple variables by specifying them one after another. In the following example, we set three different environment variables and export them at the same time:

Printing the variables outputs their value in the specified sequence.

Set a Default Value

Use the export command to assign the default value of an environment variable. For example, choose one of the 22 Best Linux text editors and change the default text editor to your preferred one.

Run the following command to set vim as the default text editor via the EDITOR variable:

Check the value of the EDITOR variable by piping the export command output to grep and searching for the EDITOR string:

The output shows the value of the EDITOR variable, which points to the vim text editor path.

Change Command Line Appearance

Change and export the value of the primary prompt PS1 variable, which defines the Bash prompt’s default structure, displaying it every time the user logs in using the terminal. The default values of PS1 are set in the /etc/bashrc file.

For example, change the prompt color by running:

The prompt color changes to green.

Export Name Value

Exporting a name value restricts it to the login shell level. Closing the command line or ending the shell session also removes the name value. Use the export command to export a name value. For example, set and export the JAVA_HOME environment variable using the following syntax:

export JAVA_HOME=/usr/share/java-x.x.x/

Replace the Java version number with the one installed on your system.

Note: Don’t have Java on your system? See how to install Java on Ubuntu.

Checking if the variable was set with echo outputs the JAVA_HOME path.

Another way to check is to grep the export command output:

The output prints the variable contents, i.e., the JAVA_HOME environment variable path.

This tutorial showed how to use the Linux export command to export the value of environment variables and functions for use in shell sessions other than the current one. Next, read our tutorial on printing a variable in Bash with printf, or see other ways of exporting variables in Bash.

Having worked as an educator and content writer, combined with his lifelong passion for all things high-tech, Bosko strives to simplify intricate concepts and make them user-friendly. That has led him to technical writing at PhoenixNAP, where he continues his mission of spreading knowledge.

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