for dir in /usr/bin /usr/sbin /sbin /bin; do
  if test -d "$dir" && ! grep -q -e "^${dir}:" -e ":${dir}:" -e ":${dir}" <<< $PATH; then
    PATH="${dir}:${PATH}"
  fi
done
export PATH

for dir in /usr/bin /usr/sbin /sbin /bin /usr/local/bin /usr/local/sbin; do
  if test -d "$dir" && ! grep -q -e "^${dir}:" -e ":${dir}:" -e ":${dir}" <<< $PATH; then
    PATH="${PATH}:${dir}"
  fi
done
export PATH

Put /usr/local/{bin,sbin} first in $PATH
[zsh] Put /usr/local/{bin,sbin} first in $PATH

This makes it easier to override some commands, like for use with
firejail.
