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LINE_CALLINFO (TAPI) (Compact 2013)

3/26/2014

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

See Also

Reference

TAPI Messages
lineClose
lineDeallocateCall
lineGetCallInfo
lineOpen
lineSetCallPrivilege
lineShutdown
LINE_CALLSTATE (TAPI)