Modification d'un format de date

$ echo 20111027191609.8Z | awk 'BEGIN{FIELDWIDTHS="4 2 2 2 2 5"}{print $1 "/" $2 "/" $3 " " $4 ":" $5 ":" $6}' 
2011/10/27 19:16:09.8Z 
$ 

$ D=20111027191609.8Z ; echo ${D:0:4}/${D:4:2}/${D:6:2} ${D:8:2}:${D:10:2}:${D:12:5} 
2011/10/27 19:16:09.8Z
$ 

var="abc"
var="${var:1}"
echo "$var"
bc

$ echo ${A%}
20111027191609.8Z

$ echo ${A%} | sed -r 's#(....)(..)(..)(..)(..)(..)(.*)#\1/\2/\3 \4:\5:\6\7#'
2011/10/27 19:16:09.8Z

$