Listing 1: The :PREP Section from SetIP.cmd

:PREP
:: Set a default IP address and assume static addressing, then check and
:: set to dhcp if needed. Set to default local area connection unless we 
:: later find the user selected wireless.
  Setlocal
  Set NicType=Local
  Set doDNS=Yes
  Set ipAddr=192.168.1.2
  Set ipMask=255.255.255.0
  Set dns=4.2.2.2
  :: Options for ipType are 'static' and 'dhcp'.
  Set ipType=static
  ::We assume the first paramater is the IP address, so let's grab it.
  If Not {%1}=={} Set ipAddr=%1 & Shift
  ::If it ends with a space, drop that character.
  If "%ipAddr:~-1,1%"==" " Set ipAddr=%ipAddr:~0,-1%
  :: Now, we have to check that it isn't actually one of the other possible 
  ::parameters. If it is, save that and revert to the original default IP address.
  If "%ipAddr%"=="mask" Set ipMask=%2 & Set ipAddr=192.168.1.2
  If "%ipAddr%"=="gw" Set ipGw=%2 & Set ipAddr=192.168.1.2
  If "%ipAddr%"=="/w" Set NicType=Wireless & Set ipAddr=192.168.1.2
  If "%ipAddr%"=="-w" Set NicType=Wireless & Set ipAddr=192.168.1.2
  If "%ipAddr%"=="/nodns" Set doDNS= & Set ipAddr=192.168.1.2
  If "%ipAddr%"=="-nodns" Set doDNS= & Set ipAddr=192.168.1.2 
  If "%ipAddr%"=="dhcp" Set ipType=source=dhcp & Set ipAddr= &
     Set dns= & Set ipMask=
  If "%ipType%"=="static" Set metric=1 & Set register=none
  Goto GetCmdLine