LINE_CALLINFO (TAPI)
A version of this page is also available for
4/8/2010
This message is sent when the call information about the specified call has changed. The application can invoke lineGetCallInfo to determine the current call information.
Syntax
LINE_CALLINFO
dwDevice = (DWORD) hCall;
dwCallbackInstance = (DWORD) hCallback;
dwParam1 = (DWORD) CallInfoState;
dwParam2 = (DWORD) 0;
dwParam3 = (DWORD) 0;
Parameters
- dwDevice
Handle to the call.
- dwCallbackInstance
Callback instance supplied when opening the call's line.
- dwParam1
Value that specifies the call information item that has changed. It can be a combination of values using the LINECALLINFOSTATE.
- dwParam2
Not used by this message. Value is NULL.
- dwParam3
Not used by this message. Value is NULL.
Return Value
None.
Remarks
A LINE_CALLINFO message with a NumOwnersIncr, NumOwnersDecr, and/or NumMonitorsChanged indication is sent to applications that already have a handle for the call. This can be the result of another application changing ownership or monitorship to a call with lineOpen, lineClose, and lineShutdown.
These LINE_CALLINFO messages are not sent when a notification of a new call is provided in a LINE_CALLSTATE (TAPI) message, because the call information already reflects the correct number of owners and monitors at the time the LINE_CALLSTATE messages are sent. LINE_CALLINFO messages are also suppressed in the case where a call is offered by TAPI to monitors through the LINECALLSTATE_UNKNOWN mechanism.
Note
The application that causes a change in the number of owners or monitors, for example, by invoking the lineDeallocateCall or lineSetCallPrivilege functions, does not itself receive a message indicating that the change has been done.
No LINE_CALLINFO messages are sent for a call after the call has entered the idle state. Specifically, changes in the number of owners and monitors are not reported as applications deallocate their handles for the idle call.
Requirements
| Header | tapi.h |
| Windows Embedded CE | Windows CE 3.0 and later |
| Windows Mobile | Windows Mobile Version 5.0 and later |
See Also
Reference
lineClose
lineDeallocateCall
lineGetCallInfo
lineOpen
lineSetCallPrivilege
lineShutdown
LINE_CALLSTATE (TAPI)