# printf 'posix PS1={%s}\n' "$PS1"
# printf 'posix PS2={%s}\n' "$PS2"
# printf 'posix PS4={%s}\n' "$PS4"
# exit
# printf 'yash PS1={%s}\n' "$PS1"
# printf 'yash PS2={%s}\n' "$PS2"
# printf 'yash PS4={%s}\n' "$PS4"
# exit
