How to programmatically determine which zsh startup file to set ZDOTDIR and XDG_CONFIG_HOME?

I want to configure zsh to read its config from ~/.config/zsh by setting ZDOTDIR=$XDG_CONFIG_HOME/zsh and ensuring XDG_CONFIG_HOME is defined early. Currently my script appends exports to three global files (/etc/profile, /etc/zshenv, /etc/zsh/zshenv) if I have sudo, otherwise symlinks ~/.zshenv.

Which files are actually needed for zsh? From the zsh manpage, only zshenv is always sourced for every zsh invocation. /etc/profile is for Bourne‑compatible shells, not zsh. Also, /etc/zshenv is the standard global file; /etc/zsh/zshenv appears only on some distributions (e.g., Debian derivatives).

How can I programmatically detect the correct file(s) to modify, instead of blindly writing to three locations? I’d like to:

• Prefer the global zshenv if I have write access (or sudo).
• Fall back to the user’s ~/.zshenv otherwise.
• Avoid touching irrelevant files like /etc/profile.

What is a reliable, cross‑distribution way to determine which path is the effective global zshenv and whether it should be used?

append_zshenv_to_global_files() {
  if ! [ -e /etc/zshenv ]; then
    sudo tee -a /etc/profile /etc/zshenv /etc/zsh/zshenv &>/dev/null <<EOF
export XDG_CONFIG_HOME=$XDG_CONFIG_HOME
export ZDOTDIR=$ZDOTDIR
EOF
  fi
}

link_zshenv_to_home_directory() {
  ln -s "$ZSHENV" "$HOME"/.zshenv
}

load_zshenv_on_startup() {
  if has_sudo; then
    append_zshenv_to_global_files
  else
    link_zshenv_to_home_directory
  fi
}

posted 4 months ago

CC BY-SA 4.0

4mo ago

ShadowsRanger‭

154 reputation 9 3 25 30