TSPI_lineMonitorDigits

This function enables and disables the unbuffered detection of digits received on the call. Each time a digit of the specified digit modes is detected, a LINE_MONITORDIGITS message is sent to the application by TAPI, indicating which digit is detected.

LONG TSPIAPI TSPI_lineMonitorDigits(
  HDRVCALL hdCall, 
  DWORD dwDigitModes 
);

Parameters

  • hdCall
    Handle to the call on which digits are to be detected. The call state of hdCall can be any state except idle or disconnected.
  • dwDigitModes
    Digit modes that are to be monitored. A dwDigitModes parameter with a value of zero cancels digit monitoring. The dwDigitModes parameter can have one of the LINEDIGITMODE constants.

Return Values

Returns zero if the function succeeds, or an error number if an error occurs.

Value Description
LINEERR_INVALCALLHANDLE The handle to the call is invalid.
LINEERR_OPERATIONUNAVAIL The operation is unavailable.
LINEERR_INVALCALLSTATE The call state is invalid.
LINEERR_OPERATIONFAILED The operation failed.
LINEERR_INVALDIGITMODE The digit mode is invalid.
LINEERR_RESOURCEUNAVAIL The resource is unavailable.
LINEERR_NOMEM Not enough memory is available.

Remarks

This function returns zero (success) when digit monitoring is correctly initiated, not when digit monitoring is terminated. Digit monitoring remains in effect until it is explicitly disabled by a call to TSPI_lineMonitorDigits with dwDigitModes set to zero, or until the call transitions to idle. The function must return zero when digit monitoring is canceled (that is, when the dwDigitModes parameter is zero). The service provider must terminate digit monitoring when the call goes idle. TAPI does not spontaneously call TSPI_lineMonitorDigits to terminate monitoring.

Although this function can be invoked in any call state, digits typically are detected only while the call is in the connected state.

Each time a digit is detected, the service provider sends a LINE_MONITORDIGITS message to TAPI, passing the detected digit as a parameter. If both LINEDIGITMODE_DTMF and LINEDIGITMODE_DTMFEND are set in dwDigitModes, the two LINE_MONITORDIGITS messages are sent for each digit.

TAPI can use TSPI_lineMonitorDigits to enable or disable unbuffered digit detection.

Requirements

OS Versions: Windows CE 3.0 and later.
Header: Tapicomn.h.
Link Library: Coredll.lib.

See Also

TSPI_lineGetDevCaps

 Last updated on Saturday, April 10, 2004

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