if [ $# -ne 1 ]; then
echo "usage: $0 FILE"
exit 1
fi
if [ -e $1 -a ! -f $1 ]; then
echo "$1 is not a file"
fi
echo -n > $1
#simpler but longer
usersdup=$(who -q|head -n 1)
for i in $userdup; do
echo $i >>userdup.txt
done
users=$(cat userdup|sort|uniq)
for user in $users; do
echo "UTENTE $user" >> $1
ps -u$user >> $1
done