LINECALLBACK callback function (tapi.h)

The lineCallback function is a placeholder for the application-supplied function name.

Syntax

LINECALLBACK Linecallback;

void Linecallback(
  DWORD hDevice,
  DWORD dwMessage,
  DWORD_PTR dwInstance,
  DWORD_PTR dwParam1,
  DWORD_PTR dwParam2,
  DWORD_PTR dwParam3
)
{...}

Parameters

hDevice

Handle to either a line device or a call associated with the callback. The nature of this handle (line handle or call handle) can be determined by the context provided by dwMsg. Applications must use the DWORD type for this parameter because using the HANDLE type may generate an error.

dwMessage

dwInstance

dwParam1

Parameter for the message.

dwParam2

Parameter for the message.

dwParam3

Parameter for the message.

Return value

None

Remarks

For information about parameter values passed to this function, see Line Device Messages.

All callbacks occur in the application's context. The callback function must reside in a DLL or application module.

Requirements

Requirement	Value
Target Platform	Windows
Header	tapi.h