etc/grml/pump-script

   1 #!/bin/sh
   2 # PUMP Script
   3 # $1 Calling circumstance (up, renewal, down)
   4 # $2 interface
   5 # $3 ip
   6
   7 # Exit early, if we're not being called for the initial lease
   8 [ "$1" != "up" ] && exit 0
   9
  10 # See if we're needed at all, only run when booted with dhcphostname
  11 for i in $(cat /proc/cmdline)
  12 do
  13         if [ "$i" = "dhcphostname" ]
  14         then
  15                 # dhcphostname is set, get the PTR for the ip
  16                 hostname=$(host $3 | awk '{ print substr($5, 0, length($5)-1) }')
  17                 if [ -n "$hostname" ]
  18                 then
  19                         echo $hostname > /etc/hostname
  20                 fi
  21         fi
  22 done