Shell Programming and Scripting

awk -F"[_.]" '{printf "\n"$NF" ";
printf substr($(NF-1),5,4) substr($(NF-1),1,4)substr($(NF-1),9)" ";
for(i=1;i<(NF-1);i++){printf $i" ";}}' infile  |
sort -nk2 |
awk '{for(i=3;i<=NF;i++) { printf $i"_";}print substr($2,5,4)substr($2,1,4)substr($2,9)"."$1}'

ls filename*|nawk '{a[$0]++} END {for(x in a) print x}' input.txt

cat testfile | sed 's/\([^0-9]*\)\([0-9]*\).csv/\1 \2 .csv /'  | sort -k2 | sed 's/ //g'

% cat testfile
MP_040420102130.csv
MP_AB_060820101450.csv
MP_CD_DE_080320101230.csv
MP_060820111230.csv
app@ubuntu ~/tmp
% cat testfile | sed 's/\([^0-9]*\)\([0-9]*\).csv/\1 \2 .csv /'  | sort -k2 | sed 's/ //g'
MP_040420102130.csv
MP_AB_060820101450.csv
MP_060820111230.csv
MP_CD_DE_080320101230.csv