SoundSentryProc
The SoundSentryProc
function is a library-defined callback function that produces a customized
visual signal when the SoundSentry accessibility feature is on and a
Windows-based application (or a non-Windows-based application running in a
window) generates a sound through the computer s built-in speaker.
LRESULT CALLBACK SoundSentryProc(
|
DWORD dwMillisec, |
// duration
of visual signal |
|
DWORD fdwEffect |
//
effect-type flag |
|
); |
|
Parameters
dwMillisec
Specifies the
duration, in milliseconds, of the visual signal that is displayed when a
Windows-based application (or a non-Windows-based application running in a
window) generates a sound.
fdwEffect
Specifies the
type of visual signal to display. Currently, this value must always be
SSWF_CUSTOM.
Return Values
If the visual
signal was or will be displayed correctly, the return value is TRUE. If the
signal is asynchronous and the status is not available when the function is
called, it should return TRUE.
If an error
prevented the signal from being displayed, the return value is FALSE. To get
extended error information, call GetLastError11C2VS7.
Remarks
The library
that contains the SoundSentryProc function must be a 32-bit DLL, and the
DLL must export a function with the name SoundSentryProc.
The SoundSentryProc
function is called only after an application or library calls the SystemParametersInfo
function, specifying the SPI_SETSOUNDSENTRY value and the address of a SOUNDSENTRY
structure whose iWindowsEffect member is set to SSWF_CUSTOM.
See Also