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access all environment variables and the values associated with them we give env command without any option

Example$ env

all the line are displayed without any new line

Exampleenv -null

gives the env version

Exampleenv --version

remove a variable from the environment

Exampleenv -uname

prints the user name

Exampleenv logname

prints all variables in the linux system

Example$ printenv

to list a specific variable just pass the name to the command

Example$ printenv SHELL

gives the path

Example$ printenv PATH

This command lists all environment variables available in your current shell session.

Exampleenv

This filters and shows only the HOME environment variable.

Exampleenv | grep HOME

TemporaryValue

Exampleenv VAR_NAME="TemporaryValue" echo $VAR_NAME

Hello World

Exampleenv VAR1="Hello" VAR2="World" bash -c 'echo "$VAR1 $VAR2"'

This shows the directories where the system looks for executable files.

Exampleenv | grep PATH

This removes VAR_NAME for the command execution but does not unset it permanently.

Exampleenv -u VAR_NAME

This starts a new bash shell with an empty environment (no variables set).

Exampleenv -i bash

This runs a bash shell as the guest user with /tmp as the home directory.

Exampleenv -i USER=guest HOME=/tmp bash

This returns the number of environment variables currently set.

Exampleenv | wc -l

This filters out system-defined environment variables and displays only custom ones.

Exampleenv | grep -vE '^(HOME|PATH|SHELL|USER|PWD|LOGNAME|TERM|LANG|DISPLAY|SSH|XDG_)'

Displays or runs a command with modified environment variables.

Example`env

Displays or sets environment variables.

Exampleenv | grep PATH

env's Examples