#!/bin/bash
BLAH=rababarabarabarara
clear

echo BLAH=$BLAH
echo 'the result of ##*ba is' ${BLAH##*ba} 
echo 'the result of #*ba is' ${BLAH#*ba} 
echo 'the result of %%ba* is' ${BLAH%%ba*}
echo 'the result of %ba* is' ${BLAH%ba*}