net

function newhost() {
    host=$1
    ipaddr=$2
    if [ -z "$host" ] || [ -z "$ipaddr" ] ; then
        echo "Usage: newhost hostname ipaddr"
        return 1
    fi
    if [ -f /tmp/newhost.lck ] ; then
        echo "There is currently a lock on newhost - "
        echo "Check that everything is OK, remove /tmp/newhost.lck, and try again."
        return 1
    fi
    touch /tmp/newhost.lck
 
    type=""
    if egrep "^[0-9\.]*[[:space:]]*${1}" /etc/hosts > /dev/null 2>&1 ; then 
        type="Updated"
        sudo sed -i "s/^.*[[:space:]]${host}/${ipaddr}   ${host}/" /etc/hosts
    else
        type="New"
        cp /etc/hosts /tmp/hosts.$$
        echo "$ipaddr    $host"  >> /tmp/hosts.$$
        sudo mv -f /tmp/hosts.$$ /etc/hosts
    fi
    echo "${type} entry: "
    grep -n "[[:space:]]${host}" /etc/hosts
    rm /tmp/newhost.lck
    return 0
}