<div class="content"><p>The NegotiateExtVersion packet is transmitted from a TAPI <a href="489de77f-16d8-4c4f-939a-f795e8b42893#gt_60e0e1fa-66fe-41e1-b5e3-ceab97e53506" data-linktype="relative-path">client</a> to a TAPI <a href="489de77f-16d8-4c4f-939a-f795e8b42893#gt_434b0234-e970-4e8c-bdfa-e16a30d96703" data-linktype="relative-path">server</a> in a <a href="489de77f-16d8-4c4f-939a-f795e8b42893#gt_8a7f6700-8311-45bc-af10-82e10accd331" data-linktype="relative-path">remote procedure call</a>.
Sending this packet MUST allow an application to negotiate an extension version
to use with the specified phone device. This operation need not be called if
the application does not support extensions.</p><table>
 <tbody><tr>
  <th><p><br/>0</p></th>
  <th><p><br/>1</p></th>
  <th><p><br/>2</p></th>
  <th><p><br/>3</p></th>
  <th><p><br/>4</p></th>
  <th><p><br/>5</p></th>
  <th><p><br/>6</p></th>
  <th><p><br/>7</p></th>
  <th><p><br/>8</p></th>
  <th><p><br/>9</p></th>
  <th><p>1<br/>0</p></th>
  <th><p><br/>1</p></th>
  <th><p><br/>2</p></th>
  <th><p><br/>3</p></th>
  <th><p><br/>4</p></th>
  <th><p><br/>5</p></th>
  <th><p><br/>6</p></th>
  <th><p><br/>7</p></th>
  <th><p><br/>8</p></th>
  <th><p><br/>9</p></th>
  <th><p>2<br/>0</p></th>
  <th><p><br/>1</p></th>
  <th><p><br/>2</p></th>
  <th><p><br/>3</p></th>
  <th><p><br/>4</p></th>
  <th><p><br/>5</p></th>
  <th><p><br/>6</p></th>
  <th><p><br/>7</p></th>
  <th><p><br/>8</p></th>
  <th><p><br/>9</p></th>
  <th><p>3<br/>0</p></th>
  <th><p><br/>1</p></th>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Req_Func</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved1</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">hPhoneApp</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">dwDeviceID</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">dwTSPIVersion</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">dwLowVersion</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">dwHighVersion</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">lpdwExtVersion</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved2</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved3</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved4</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved5</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved6</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved7</p>
  </td>
 </tr>
 <tr>
  <td colspan="32">
  <p align="center">Reserved8</p>
  </td>
 </tr>
</tbody></table><p><b>Req_Func (4 bytes): </b>The identifier of the
function that will be invoked on the remote server. This value MUST be set to
109.</p><dl>
<dd>
<p><b>Return Values</b></p>
</dd>
<dd>
<p>On completion of <a href="c28c36d0-579b-4e20-a100-f4e71012d5f8" data-linktype="relative-path">ClientRequest</a>, this field
MUST contain the result of the encapsulated telephony request. A value of 0
indicates success, and a <a href="b1c6fae0-09ca-4f7b-85f6-1324376d231c" data-linktype="relative-path">PHONEERR_Constants</a>
value indicates failure. The remote server MUST complete this call
synchronously.</p>
</dd>
<dd>
<p>Returns 0 if the request succeeds or a negative
error number if an error occurs. The following table lists common return
values.</p>
</dd>
<dd>
<table><thead>
  <tr>
   <th>
   <p>Name</p>
   </th>
   <th>
   <p>Value</p>
   </th>
  </tr>
 </thead><tbody><tr>
  <td>
  <p>PHONEERR_INVALAPPHANDLE</p>
  </td>
  <td>
  <p>0x00000007</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_OPERATIONFAILED</p>
  </td>
  <td>
  <p>0x0000001C</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_BADDEVICEID</p>
  </td>
  <td>
  <p>0x00000002</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_OPERATIONUNAVAIL</p>
  </td>
  <td>
  <p>0x0000001D</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_NODRIVER</p>
  </td>
  <td>
  <p>0x00000019</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_NOMEM</p>
  </td>
  <td>
  <p>0x0000001A</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_INCOMPATIBLEAPIVERSION</p>
  </td>
  <td>
  <p>0x00000003</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_RESOURCEUNAVAIL</p>
  </td>
  <td>
  <p>0x0000001F</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_INCOMPATIBLEEXTVERSION</p>
  </td>
  <td>
  <p>0x00000004</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_UNINITIALIZED</p>
  </td>
  <td>
  <p>0x00000022</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_INVALPOINTER</p>
  </td>
  <td>
  <p>0x00000015</p>
  </td>
 </tr><tr>
  <td>
  <p>PHONEERR_NODEVICE</p>
  </td>
  <td>
  <p>0x00000018</p>
  </td>
 </tr></tbody></table>
</dd></dl><p><b>Reserved1 (4 bytes): </b>An unsigned 32-bit
integer. MUST be set to zero when sent and MUST be ignored on receipt. </p><p><b>hPhoneApp (4 bytes): </b>An <a href="55b72ff6-9236-401b-846a-e8a78dfada1b" data-linktype="relative-path">HPHONEAPP</a>. The handle to
the application registration with TAPI. This field MUST have been obtained by
sending the <a href="a600d262-0bb1-447b-8a0d-6f57d3a8ec18" data-linktype="relative-path">Initialize</a>
packet.</p><p><b>dwDeviceID (4 bytes): </b>An unsigned 32-bit
integer. The identifier of the phone device to be queried. A valid value of
dwDeviceID is in the range 0 to dwNumDevs –1. The client obtains dwNumDevs by
sending a Initialize packet to the remote server.</p><p><b>dwTSPIVersion (4 bytes): </b>An unsigned 32-bit
integer. The TAPI version number that was negotiated for the specified phone
device by using <a href="59e34869-7701-4eb5-95d4-f8ce908ce17a" data-linktype="relative-path">NegotiateAPIVersion</a>.
</p><p><b>dwLowVersion (4 bytes): </b>An unsigned 32-bit
integer. The least recent extension version of the extension identifier that is
returned by NegotiateAPIVersion and with which the application is compliant.
The high-order word is the major version number; the low-order word is the minor
version number. </p><p><b>dwHighVersion (4 bytes): </b>An unsigned 32-bit
integer. The most recent extension version of the extension identifier that is
returned by NegotiateAPIVersion and with which the application is compliant.
The high-order word is the major version number; the low-order word is the
minor version number.</p><p><b>lpdwExtVersion (4 bytes): </b>An unsigned 32-bit
integer. Set to TAPI_NO_DATA (0xFFFFFFFF). Upon successful completion of the
request, this field contains the highest extension version number, within the
range that is requested by the caller, under which the service provider can
operate. The most-significant WORD is the major version number and the
least-significant WORD is the minor version number.</p><p><b>Reserved2 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved3 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved4 (4 bytes): </b>An unsigned 32-bit integer.
This field is used for padding and MUST be ignored on receipt. It can be any
value.</p><p><b>Reserved5 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved6 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved7 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p><p><b>Reserved8 (4 bytes): </b>An unsigned 32-bit
integer. This field is used for padding and MUST be ignored on receipt. It can
be any value.</p></div>