#!/bin/sh  make_resolv_conf() {  if [ x"$new_domain_name_servers" != x ]; then    cat /dev/null > /etc/resolv.conf.dhclient    if [ x"$new_domain_search" != x ]; then      echo search $new_domain_search >> /etc/resolv.conf.dhclient    elif [ x"$new_domain_name" != x ]; then      # Note that the DHCP 'Domain Name Option' is really just a domain      # name, and that this practice of using the domain name option as      # a search path is both nonstandard and deprecated.      echo search $new_domain_name >> /etc/resolv.conf.dhclient    fi    for nameserver in $new_domain_name_servers; do      echo nameserver $nameserver >>/etc/resolv.conf.dhclient    done    mv /etc/resolv.conf.dhclient /etc/resolv.conf  fi}# Must be used on exit.   Invokes the local dhcp client exit hooks, if any.exit_with_hooks() {  exit_status=$1  if [ -f /etc/dhclient-exit-hooks ]; then    . /etc/dhclient-exit-hooks  fi# probably should do something with exit status of the local script  exit $exit_status}# Invoke the local dhcp client enter hooks, if they exist.if [ -f /etc/dhclient-enter-hooks ]; then  exit_status=0  . /etc/dhclient-enter-hooks  # allow the local script to abort processing of this state  # local script must set exit_status variable to nonzero.  if [ $exit_status -ne 0 ]; then    exit $exit_status  fifiif [ x$new_broadcast_address != x ]; then  new_broadcast_arg="broadcast $new_broadcast_address"fiif [ x$old_broadcast_address != x ]; then  old_broadcast_arg="broadcast $old_broadcast_address"fiif [ x$new_subnet_mask != x ]; then  new_netmask_arg="netmask $new_subnet_mask"fiif [ x$old_subnet_mask != x ]; then  old_netmask_arg="netmask $old_subnet_mask"fiif [ x$alias_subnet_mask != x ]; then  alias_subnet_arg="netmask $alias_subnet_mask"fiifconfig=/sbin/ifconfigrelease=`uname -r`release=`expr $release : '\(.*\)\..*'`relmajor=`echo $release |sed -e 's/^\([^\.]*\)\..*$/\1/'`relminor=`echo $release |sed -e 's/^.*\.\([^\.]*\)$/\1/'`if [ x$reason = xMEDIUM ]; then  eval "$ifconfig $interface $medium"  $ifconfig $interface  sleep 1  exit_with_hooks 0fiif [ x$reason = xPREINIT ]; then  if [ x$alias_ip_address != x ]; then    $ifconfig ${interface}:1 0 down > /dev/null 2>&1    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1  fi  if [ $relmajor -gt 5 ] || ( [ $relmajor -eq 5 ] && [ $relminor -ge 5 ] )  then	  # Turn the interface on	  $ifconfig $interface plumb	  $ifconfig $interface up  else      $ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 \              broadcast 255.255.255.255 up  fi   exit_with_hooks 0fiif [ x$reason = xARPCHECK ] || [ x$reason = xARPSEND ]; then  exit_with_hooks 0;fi  if [ x$reason = xBOUND ] || [ x$reason = xRENEW ] || \   [ x$reason = xREBIND ] || [ x$reason = xREBOOT ]; then  current_hostname=`hostname`  if [ x$current_hostname = x ] || \     [ x$current_hostname = x$old_host_name ]; then    if [ x$current_hostname = x ] || \       [ x$new_host_name != x$old_host_name ]; then      hostname $new_host_name    fi  fi      if [ x$old_ip_address != x ] && [ x$alias_ip_address != x ] && \		[ x$alias_ip_address != x$old_ip_address ]; then    $ifconfig ${interface}:1 inet 0 down > /dev/null 2>&1    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1  fi  if [ x$old_ip_address != x ] && [ x$old_ip_address != x$new_ip_address ]; then    $ifconfig ${interface} inet 0 down    route delete $old_ip_address 127.1 >/dev/null 2>&1    for router in $old_routers; do      route delete default $router >/dev/null 2>&1    done  fi  if [ x$old_ip_address = x ] || [ x$old_ip_address != x$new_ip_address ] || \     [ x$reason = xBOUND ] || [ x$reason = xREBOOT ]; then    eval "$ifconfig $interface inet $new_ip_address $new_netmask_arg \					$new_broadcast_arg $medium"    route add $new_ip_address 127.1 1 >/dev/null 2>&1    for router in $new_routers; do      route add default $router 1 >/dev/null 2>&1    done  fi  if [ x$new_ip_address != x$alias_ip_address ] && [ x$alias_ip_address != x ];   then    $ifconfig ${interface}:1 inet $alias_ip_address $alias_subnet_arg    route add $alias_ip_address 127.0.0.1 1  fi  make_resolv_conf  exit_with_hooks 0fiif [ x$reason = xEXPIRE ] || [ x$reason = xFAIL ] || [ x$reason = xRELEASE ] \   || [ x$reason = xSTOP ]; then  if [ x$alias_ip_address != x ]; then    $ifconfig ${interface}:1 0 down > /dev/null 2>&1    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1  fi  if [ x$old_ip_address != x ]; then    $ifconfig $interface inet 0 down    route delete $old_ip_address 127.1 >/dev/null 2>&1    for router in $old_routers; do      route delete default $router >/dev/null 2>&1    done  fi  if [ x$alias_ip_address != x ]; then    $ifconfig ${interface}:1 inet $alias_ip_address $alias_subnet_arg    route add $alias_ip_address 127.0.0.1 1  fi  exit_with_hooks 0fiif [ x$reason = xTIMEOUT ]; then  if [ x$alias_ip_address != x ]; then    $ifconfig ${interface}:1 0 down > /dev/null 2>&1    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1  fi  eval "$ifconfig $interface inet $new_ip_address $new_netmask_arg \					$new_broadcast_arg $medium"  sleep 1  set $new_routers  if ping -s -n -I 1 $1 64 1; then    if [ x$new_ip_address != x$alias_ip_address ] && \			[ x$alias_ip_address != x ]; then      $ifconfig ${interface}:1 inet $alias_ip_address $alias_subnet_arg      route add $alias_ip_address 127.0.0.1 1    fi    route add $new_ip_address 127.1 1 >/dev/null 2>&1    for router in $new_routers; do      route add default $router 1 >/dev/null 2>&1    done    make_resolv_conf    exit_with_hooks 0  fi  $ifconfig $interface inet 0 down  for router in $old_routers; do    route delete default $router >/dev/null 2>&1  done  exit_with_hooks 1fiexit_with_hooks 0