Problems with graceful shutdown of dhclient

[Dallas Clement]

Hello All,

I'm having troubles getting my dhclient to exit gracefully when the
interface has not yet been configured with an IP address.

The computer which is running dhclient is attached to an ethernet switch.
When the link is up, I start dhclient.  However, there is no DHCP server
attached to this switch and hence dhclient fails to get a lease.  If I pull
out my ethernet cable forcing the link down, I try to gracefully stop
dhclient.  For some reason neither the -x or -r options are working for me.
The dhclient -x returns 0 -- which I am assuming means success.  However,
the dhclient daemon process continues to execute and does not remove its PID
file.

Is the -x option only applicable after a lease has been obtained?  Maybe I'm
doing something stupid, but it's not obvious to me.  Any help greatly
appreciated!

~Dallas

===============

Here is a snippet of the script file which performs these actions:

DHCP_CONF_FILE="/tmp/dhclient.${IFACE_NAME}.conf"
DHCP_PID_FILE="/tmp/dhclient.${IFACE_NAME}.pid"
DHCP_LEASE_FILE="/tmp/dhclient.${IFACE_NAME}.leases"
DHCP_SCRIPT="/etc/dhclient-script"

linkup()
{
   if [ x$IFACE_NAME != x ]; then
      if [ $DHCP_ENABLED -eq 1 ]; then
         # Create DHCP configuration file
         echo "interface \"$IFACE_NAME\" {" > $DHCP_CONF_FILE
         echo "}" >> $DHCP_CONF_FILE
         # Start an instance of the DHCP daemon for this interface
         dhclient -nw -pf $DHCP_PID_FILE -lf $DHCP_LEASE_FILE \
         -cf $DHCP_CONF_FILE -sf $DHCP_SCRIPT $IFACE_NAME
      else # DHCP is disabled
         ifconfig $IFACE_NAME $IP_ADDRESS netmask $NETMASK
      fi
   fi
}

linkdown()
{
   if [ x$IFACE_NAME != x ]; then
      if [ $DHCP_ENABLED -eq 1 ]; then
         dhclient -x -pf $DHCP_PID_FILE -lf $DHCP_LEASE_FILE \
         -cf $DHCP_CONF_FILE -sf $DHCP_SCRIPT $IFACE_NAME
         if [ $? -eq 0 ]; then
            while [ -f "$DHCP_PID_FILE" ]; do
               sleep 1
            done
            rm $DHCP_LEASE_FILE
         fi
      fi
   fi
}
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