#! /bin/zsh -f

# user-add-group mmc foto

if [ $# -le 1 ]
then
echo insufficient arguments $#
echo usage: user-add-group mmc foto
exit -1
else
user=$1
group=$2

groups $user
usermod -a -G $group $user
# usermod -G $(groups ${user} |sed -e 's/ /,/g'),${group} $user
groups $user
fi