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4/8/2010

This function sends Dual-Tone Multifrequency (DTMF) tones across an established voice call.

Syntax 

HRESULT RIL_SendDTMF(
  HRIL 
hRil,
  LPCSTR 
lpszChars,
  DWORD 
dwDuration
);

Parameters

hRil

Handle to the RIL instance returned by RIL_Initialize.

lpszChars

Alphanumeric string representing DTMF tones to be sent. If the string contains multiple characters, each tone is played sequentially. Set to RIL_DTMFDURATION_DEFAULT.

dwDuration

Specifies the new DTMF tone duration in milliseconds. Although Microsoft does not set a requirement for tone duration, the RIL sample driver uses a default value of 3 seconds.

Return Value

Positive HRESULTvalues indicate success and are used as command identifications for matching the asynchronous call result. Negative HRESULTvalues indicate an error. Errors are defined in the Ril.h file.

An asychronous result of RIL_RESULT_OKindicates success. The lpDatanotification parameter is set to NULL.

Remarks

This function does not return until the DTMF tone has completed.

The RIL proxy translates the RIL_SendDTMFfunction into IOCTL_RIL_SendDTMFwhen the RIL proxy calls RIL_IOControl.

Requirements

Header ril.h
Library Ril.lib
Windows Embedded CE Windows CE .NET 4.2 and later

See Also

Reference

RIL_Initialize