#!/bin/sh
# sum of $1 file

if [ ! -z "$1" ]; then 
    SM=`du -B M -s *.$1 | awk '{print $1}' | perl -pi -e "s/M\n/+/g"`
    T=`echo "$SM"0 | bc -l`
    echo " Total des fichiers *.$1 de:"
    echo "$T Mo"
    
else
    echo
    echo " First arg must be an extension"
    echo
fi