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+udhcp client (udhcpc)
+--------------------
+
+The udhcp client negotiates a lease with the DHCP server and notifies
+a set of scripts when a leases is obtained or lost.
+
+
+command line options
+-------------------
+
+The command line options for the udhcp client are:
+
+-c, --clientid=CLIENTID         Set client identifier.  Type is first char.
+-C, --clientid-none             Suppress default client identifier
+-V, --vendorclass=CLASSID       Set vendor class identifier
+-H, --hostname=HOSTNAME         Client hostname
+-h,                             Alias for -H
+-F, --fqdn=FQDN                 Client fully qualified domain name
+-f, --foreground                Do not fork after getting lease
+-b, --background                Fork to background if lease cannot be
+                                immediately negotiated.
+-i, --interface=INTERFACE       Interface to use (default: eth0)
+-n, --now                       Exit with failure if lease cannot be
+                                immediately negotiated.
+-p, --pidfile=file              Store process ID of daemon in file
+-q, --quit                      Quit after obtaining lease
+-r, --request=IP                IP address to request (default: none)
+-s, --script=file               Run file at dhcp events (default:
+                                /usr/share/udhcpc/default.script)
+-v, --version                   Display version
+
+
+If the requested IP address cannot be obtained, the client accepts the
+address that the server offers.
+
+
+udhcp client scripts
+-------------------
+
+When an event occurs, udhcpc calls the action script. udhcpc never does
+any configuration of the network interface itself, but instead relies on
+a set of scripts. The script by default is
+/usr/share/udhcpc/default.script but this can be changed via the command
+line arguments. The three possible arguments to the script are:
+
+        deconfig: This argument is used when udhcpc starts, and
+        when a leases is lost. The script must put the interface in an
+        up, but deconfigured state, ie: ifconfig $interface 0.0.0.0.
+
+        bound: This argument is used when udhcpc moves from an
+        unbound, to a bound state. All of the paramaters are set in
+        enviromental variables, The script should configure the interface,
+        and set any other relavent parameters (default gateway, dns server,
+        etc).
+
+        renew: This argument is used when a DHCP lease is renewed. All of
+        the paramaters are set in enviromental variables. This argument is
+        used when the interface is already configured, so the IP address,
+        will not change, however, the other DHCP paramaters, such as the
+        default gateway, subnet mask, and dns server may change.
+
+        nak: This argument is used with udhcpc receives a NAK message.
+        The script with the deconfig argument will be called directly
+        afterwards, so no changes to the network interface are neccessary.
+        This hook is provided for purely informational purposes (the
+        message option may contain a reason for the NAK).
+
+The paramaters for enviromental variables are as follows:
+
+        $HOME           - The set $HOME env or "/"
+        $PATH           - the set $PATH env or "/bin:/usr/bin:/sbin:/usr/sbin"
+        $1              - What action the script should perform
+        interface       - The interface this was obtained on
+        ip              - The obtained IP
+        mask            - The number of bits in the netmask (ie: 24)
+        siaddr          - The bootp next server option
+        sname           - The bootp server name option
+        boot_file       - The bootp boot file option
+        subnet          - The assigend subnet mask
+        timezone        - Offset in seconds from UTC
+        router          - A list of routers
+        timesvr         - A list of time servers
+        namesvr         - A list of IEN 116 name servers
+        dns             - A list of DNS server
+        logsvr          - A list of MIT-LCS UDP log servers
+        cookiesvr       - A list of RFC 865 cookie servers
+        lprsvr          - A list of LPR servers
+        hostname        - The assigned hostname
+        bootsize        - The length in 512 octect blocks of the bootfile
+        domain          - The domain name of the network
+        swapsvr         - The IP address of the client's swap server
+        rootpath        - The path name of the client's root disk
+        ipttl           - The TTL to use for this network
+        mtu             - The MTU to use for this network
+        broadcast       - The broadcast address for this network
+        ntpsrv          - A list of NTP servers
+        wins            - A list of WINS servers
+        lease           - The lease time, in seconds
+        dhcptype        - DHCP message type (safely ignored)
+        serverid        - The IP of the server
+        message         - Reason for a DHCPNAK
+        tftp            - The TFTP server name
+        bootfile        - The bootfile name
+
+additional options are easily added in options.c.
+
+
+note on udhcpc's random seed
+---------------------------
+
+udhcpc will seed its random number generator (used for generating xid's)
+by reading /dev/urandom. If you have a lot of embedded systems on the same
+network, with no entropy, you can either seed /dev/urandom by a method of
+your own, or doing the following on startup:
+
+ifconfig eth0 > /dev/urandom
+
+in order to seed /dev/urandom with some data (mac address) unique to your
+system. If reading /dev/urandom fails, udhcpc will fall back to its old
+behavior of seeding with time(0).
+
+
+signals accepted by udhcpc
+-------------------------
+
+udhcpc also responds to SIGUSR1 and SIGUSR2. SIGUSR1 will force a renew state,
+and SIGUSR2 will force a release of the current lease, and cause udhcpc to
+go into an inactive state (until it is killed, or receives a SIGUSR1). You do
+not need to sleep between sending signals, as signals received are processed
+sequencially in the order they are received.
+
+
+compile time options
+-------------------
+
+options.c contains a set of dhcp options for the client:
+
+        name[10]: The name of the option as it will appear in scripts
+
+        flags: The type of option, as well as if it will be requested
+        by the client (OPTION_REQ)
+
+        code: The DHCP code for this option
+