Environment variables

Linux environment variables

Arch Wiki: environment variables

System-wide

• /etc/profile is sourced by all POSIX-compatible shells upon login.
• Files inside the /etc/profile.d/ directory will also be read.

Bash

• ~/.profile or ~/.bash_profile for login bash instances.
• ~/.bashrc for every interactive bash instance.

Zsh

• ~/.zshenv for environment variables in all zsh instances.
• ~/.zprofile for every login zsh instance.
• ~/.zshrc for every interactive zsh instance.

skip_global_compinit=1
test -r ${HOME}/.profile && emulate sh -c 'source ${HOME}/.profile'

X Window

• ~/.xinitrc is sourced by startx.
• ~/.xprofile is sourced by display managers (e.g., GDM, SDDM)

Systemd and Wayland

• ~/.config/environment.d/*.conf: sourced by systemd. Also, they are used in Wayland sessions where xinitrc and xprofile files are not available.

Windows environment variables

Environment variables in Powershell

Session variables

Variables created by set are bound to the current session and not persistent.

$Env:FOO = "example"
$Env:FOO

Persistent variables

• GUI: Windows Settings -> Advanced system settings -> Set Environment Variables.
• Powershell: [Environment]::SetEnvironmentVariable('KEY', 'VAL', 'Machine')
• Cmd: SETX KEY VAL