View source for HM UPDATE OBJCOM WINDOW CHAIN

{{DISPLAYTITLE:HM_UPDATE_OBJCOM_WINDOW_CHAIN}}
This message is sent to the currently active communication object by the communication object who wants to withdraw from the communication chain.

==Syntax==
<pre>
param1
HWND hwnd; /* The handle of the object to be withdrawn from the communication chain. */

param2
HWND hwnd; /* Window containing the handle of the object to be replaced. */
</pre>

==Parameters==
;hwnd ([[HWND]]) - input: The handle of the object to be withdrawn from the communication
::chain.
;hwnd ([[HWND]]) - input: Window containing the handle of the object to be replaced.

==Returns==
;ulReserved ([[ULONG]]) - return: Reserved value, should be 0.

==Remarks==
The object that receives this message should check to see if the object handle returned from [[HM_SET_OBJCOM_WINDOW]] is equal to the handle in '''param1'''. If the handle is equal, then the handle in '''param1''' should be replaced by the handle in '''param2'''. If the handle is not equal and the handle previously received is not NULL HANDLE, then send HM_UPDATE_OBJCOM_WINDOW_CHAIN to that object.

==Default Processing==
None.

[[Category:Messages]]