./postconf: warning: ./main.cf: undefined parameter: z ./postconf: warning: ./main.cf: undefined parameter: z bar = y-value baz = config_directory = . t1 = Postfix 2.11 compatible x = x-value y = y-value ./postconf: warning: ./main.cf: unused parameter: t2=$t1 ./postconf: warning: ./main.cf: unused parameter: foo=$bar$baz