env Cheatsheet
Basic Syntax
Core env command forms.
| Command | Description |
|---|---|
env |
Print the current environment |
env --help |
Show available options |
env --version |
Show the installed env version |
env -0 |
Print variables separated with NUL bytes |
Inspect Environment Variables
Use env with filters to inspect specific variables.
| Command | Description |
|---|---|
| `env | sort` |
| `env | grep ‘^PATH=’` |
| `env | grep ‘^HOME=’` |
| `env | grep ‘^LANG=’` |
Run Commands with Temporary Variables
Set variables for one command without changing the current shell session.
| Command | Description |
|---|---|
VAR=value env command |
Run one command with a temporary variable |
VAR1=dev VAR2=1 env command |
Set multiple temporary variables |
env PATH=/custom/bin:$PATH command |
Override PATH for one command |
env LANG=C command |
Run a command with the C locale |
env HOME=/tmp bash |
Start a shell with a temporary home directory |
Clean or Remove Variables
Start with a minimal environment or remove selected variables.
| Command | Description |
|---|---|
env -i command |
Run a command with an empty environment |
env -i PATH=/usr/bin:/bin bash --noprofile --norc |
Start a mostly clean shell with a minimal PATH |
env -u VAR command |
Run a command without one variable |
env -u http_proxy command |
Remove a proxy variable for one command |
env -i VAR=value command |
Run a command with only the variables you set explicitly |
Common Variables
These variables are often inspected or overridden with env.
| Variable | Description |
|---|---|
PATH |
Directories searched for commands |
HOME |
Current user’s home directory |
USER |
Current user name |
SHELL |
Default login shell |
LANG |
Locale and language setting |
TZ |
System timezone (e.g. America/New_York) |
EDITOR |
Default text editor |
TERM |
Terminal type (e.g. xterm-256color) |
TMPDIR |
Directory for temporary files |
PWD |
Current working directory |
Troubleshooting
Quick checks for common env issues.
| Issue | Check |
|---|---|
| A temporary variable does not persist | env VAR=value command affects only that command and its children |
A command is not found after env -i |
Add a minimal PATH, such as /usr/bin:/bin |
| Output is hard to parse safely | Use env -0 with tools that support NUL-delimited input |
| A variable is still visible in the shell | env does not modify the parent shell; use export or unset the variable in the shell itself |
| A locale-sensitive command behaves differently | Check whether LANG or related locale variables were overridden |
Related Guides
Use these guides for broader environment-variable workflows.
| Guide | Description |
|---|---|
| How to Set and List Environment Variables in Linux | Full guide to listing and setting environment variables |
| export Command in Linux | Export shell variables to child processes |
| Bashrc vs Bash Profile | Understand shell startup files |
| Bash cheatsheet | Quick reference for Bash syntax and variables |
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