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initial lease negotiation until that process is complete.  In addition, any 
addressing information obtained will be applied to that network interface, 
which will remain disabled if the initial negotiation fails.  Finally, the
interface will be disabled if the lease expires.
<p>
</blockquote><h4>NOTE</h4><blockquote><p>
If the DHCP client is used to obtain the VxWorks boot parameters, this 
routine is called automatically during system startup using the automatic 
reconfiguration.  Therefore, any calls to this routine which use the network 
boot device for message transfer when the DHCP client was used at boot time 
must not request automatic reconfiguration during initialization.  Otherwise, 
the resulting lease settings will conflict with the configuration maintained 
by the lease established during system startup. 
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if routine completes, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_BAD_OPTION
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>

<hr>
<a name="dhcpcVerify"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>dhcpcVerify</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>dhcpcVerify</i>(&nbsp;)</strong> - renew an established lease</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS dhcpcVerify
    (
    void * pCookie /* identifier returned by dhcpcInit() */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine schedules the lease identified by the <i>pCookie</i> parameter
for immediate renewal according to the process described in RFC 1541.
If the renewal is unsuccessful, the lease negotiation process restarts.
The routine is valid as long as the lease is currently active.  The
routine is also called automatically in response to a <b><i><a href="./dhcpcLib.html#dhcpcBind">dhcpcBind</a></i>(&nbsp;)</b> call
for an existing lease.
<p>
</blockquote><h4>NOTE</h4><blockquote><p>
This routine will disable the underlying network interface if the 
verification fails and automatic configuration was requested.  This may
occur without warning if no event hook is installed.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if verification scheduled, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>

<hr>
<a name="dhcpcRelease"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>dhcpcRelease</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>dhcpcRelease</i>(&nbsp;)</strong> - relinquish specified lease</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS dhcpcRelease
    (
    void * pCookie /* identifier returned by dhcpcInit() */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine schedules the lease identified by the <i>pCookie</i> parameter
for immediate release, regardless of time remaining, and removes all
the associated data structures.  After the release completes, a new
call to <b><i><a href="./dhcpcLib.html#dhcpcInit">dhcpcInit</a></i>(&nbsp;)</b> is required before attempting another lease.
<p>
</blockquote><h4>NOTE</h4><blockquote><p>
This routine will disable the underlying network interface if automatic 
configuration was requested.  This may occur without warning if no event 
hook is installed.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if release scheduled, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>

<hr>
<a name="dhcpcShutdown"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>dhcpcShutdown</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>dhcpcShutdown</i>(&nbsp;)</strong> - disable DHCP client library</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>

STATUS dhcpcShutdown (void)</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine schedules the lease monitor task to clean up memory and exit,
after releasing all currently active leases.  The network boot device
will be disabled if the DHCP client was used to obtain the VxWorks boot 
parameters and the resulting lease is still active.  Any other interfaces 
using the addressing information from leases set for automatic configuration
will also be disabled.  Notification of a disabled interface will not occur
unless an event hook has been installed.  After the processing started by
this request completes, the DHCP client library is unavailable until 
restarted with the <b><i><a href="./dhcpcLib.html#dhcpcLibInit">dhcpcLibInit</a></i>(&nbsp;)</b> routine.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if shutdown scheduled, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_NOT_INITIALIZED
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>

<hr>
<a name="dhcpcOptionGet"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>dhcpcOptionGet</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>dhcpcOptionGet</i>(&nbsp;)</strong> - retrieve an option provided to a client and store in a buffer</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS dhcpcOptionGet
    (
    void * pCookie, /* identifier returned by dhcpcInit() */
    int    option,  /* RFC 1533 option tag */
    int *  pLength, /* size of provided buffer and data returned */
    char * pBuf     /* location for option data */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine retrieves the data for the specified <i>option</i>, if present
for the lease indicated by <i>pCookie</i>.  The data is stored in the provided 
buffer, whose length must be specified.  If the <i>option</i> is found, the amount 
of data available is stored in the location referenced by the <i>pLength</i> 
parameter.  The option is not available if the DHCP client is not in the 
bound state or if the server did not provide it.  After returning, the 
provided buffer may contain IP addresses stored in network byte order.  All 
other numeric values are stored in host byte order.  See RFC 1533 for specific
details on the data retrieved. 
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if option available, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND,<br>
&nbsp;S_dhcpcLib_OPTION_NOT_PRESENT
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>, <b><i><a href="./dhcpcLib.html#dhcpcOptionSet">dhcpcOptionSet</a></i>(&nbsp;)</b>

<hr>
<a name="dhcpcServerGet"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>dhcpcServerGet</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>dhcpcServerGet</i>(&nbsp;)</strong> - retrieve the current DHCP server</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS dhcpcServerGet
    (
    void *           pCookie,    /* identifier returned by dhcpcInit() */
    struct in_addr * pServerAddr /* location for address of server */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine returns the DHCP server that supplied the configuration
parameters for the lease specified by the <i>pCookie</i> argument.  This 
information is available only if the lease is in the bound state.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if in bound state and server available, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>

<hr>
<a name="dhcpcTimerGet"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>dhcpcTimerGet</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>dhcpcTimerGet</i>(&nbsp;)</strong> - retrieve current lease timers</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS dhcpcTimerGet
    (
    void * pCookie, /* identifier returned by dhcpcInit() */
    int *  pT1,     /* time until lease renewal */
    int *  pT2      /* time until lease rebinding */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine returns the number of clock ticks remaining on the timers
governing the DHCP lease specified by the <i>pCookie</i> argument.  This 
information is only available if the lease is in the bound state.
Therefore, this routine will return ERROR if a BOOTP reply was accepted.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if in bound state and values available, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND, <br>
&nbsp;S_dhcpcLib_OPTION_NOT_PRESENT,&nbsp;S_dhcpcLib_TIMER_ERROR
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>

<hr>
<a name="dhcpcParamsGet"></a>
<p align=right>
<a href="rtnIndex.html"><i>Libraries :  Routines</i></a></p>

</blockquote><h1><i>dhcpcParamsGet</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>dhcpcParamsGet</i>(&nbsp;)</strong> - retrieve current configuration parameters</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS dhcpcParamsGet
    (
    void *              pCookie,   /* identifier returned by dhcpcInit() */
    struct dhcp_param * pParamList /* requested parameters */
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine copies the current configuration parameters for the lease
specified by the <i>pCookie</i> argument to the user-supplied structure.  That 
structure, defined in <b>dhcp/dhcpc.h</b>, should contain non-NULL pointers to 
indicate the parameters of interest.  All other values within the structure 
must be set to 0 before calling the routine.  The requested information is 
only retrieved if the specified lease is in the bound state and knows that 
its parameters are good.
<p>
Many of the parameters within the user-supplied structure use one of the 
following secondary data types: struct in_addrs, struct u_shorts, and 
struct vendor_list.  Each of those structures accepts a length designation 
and a data pointer.  For the first two data types, the <b>num</b> member indicates 
the size of the buffer in terms of the number of underlying elements.  For 
example, the <b>STATIC_ROUTE</b> option returns one or more IP address pairs.  So, 
setting the <b>num</b> member to 2 in the static_route entry would indicate that 
the corresponding buffer contained 16 bytes.  By contrast, the <b>len</b> member 
in the struct <b>vendor_list</b> data type consists of the buffer size, in bytes.
See RFC 1533 for specific details on the types of data for each option. 
<p>
On return, each of the length designators are set to indicate the amount of
data returned.  For instance, the <b>num</b> member in the static_route entry could
be set to 1 to indicate that only one IP address pair of 8 bytes was 
available.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK if in bound state, or ERROR otherwise.
<p>
</blockquote><h4>ERRNO</h4><blockquote><p>
S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./dhcpcLib.html#top">dhcpcLib</a></b>

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