for cdnr in CD* ; do cd "$cdnr" cdnum=$(echo $cdnr|sed -e 's/CD //'); low=$(ls|sed -e 's/.mp3//' -e 's/^0*//'|sort -n|head -1) high=$(ls|sed -e 's/.mp3//' -e 's/^0*//'|sort -n|tail -1) num=1 for i in $(seq -w $low $high) ; do count=$(echo $num|sed -e 's/^\(.\)$/0\1/') mv *$i.mp3 "../Perry Rhodan - Silber Edition 13 - Der Zielstern CD${cdnum} ${count}.mp3" num=$(($num+1)) done cd .. done