env

The "env" command line tool is used to display or set environment variables in a Unix-like operating system. It can also run a command with modified environment variables.

Here are some key features and usage examples of the "env" command:

1. Display current environment variables: Running the "env" command without any arguments will display the current environment variables with their respective values.

2. Set environment variables: The command can be used to set new environment variables or modify existing ones in the current shell environment. For example:

   • To set the variable "MY_VAR" with the value "hello": env MY_VAR=hello
   • To modify the existing variable "PATH" by adding a new directory: env PATH=$PATH:/new/directory

3. Run a command with modified environment variables: By prefixing a command with the "env" command, you can run it with modified environment variables. For example:

   • To run a command with a specific environment variable: env VAR_NAME=value command
   • To unset an environment variable before running a command: env -u VAR_NAME command

4. Invoke scripts with desired environment variables: The "env" command is often used to invoke scripts with specific environment variables required for their execution.

5. Portability and compatibility: The "env" command ensures portability by allowing scripts or commands to run with consistent environment variable settings across different systems.

6. Searching for executables in different locations: The "env" command can be used to search for executables in different directories by manipulating the "PATH" variable.

Overall, the "env" command provides a flexible way to manage and manipulate environment variables, which are essential for configuring the behavior of various applications and scripts in a Unix-like environment.