The SOUNDSENTRY structure contains information about the SoundSentry accessibility feature. When the SoundSentry feature is on, the computer displays a visual indication only when a sound is generated.
Windows 95: The visual indication is displayed when a sound is generated through the computer's internal speaker.
Windows NT: The visual indication is displayed when a sound is generated through either the multimedia sound services or through the computer's speaker.
typedef struct tagSOUNDSENTRY { // ss
UINT cbSize;
DWORD dwFlags;
DWORD iFSTextEffect;
DWORD iFSTextEffectMSec;
DWORD iFSTextEffectColorBits;
DWORD iFSGrafEffect;
DWORD iFSGrafEffectMSec;
DWORD iFSGrafEffectColor;
DWORD iWindowsEffect;
DWORD iWindowsEffectMSec;
LPTSTR lpszWindowsEffectDLL;
DWORD iWindowsEffectOrdinal;
} SOUNDSENTRY, *LPSOUNDSENTRY;
Members
cbSize
Specifies the size, in bytes, of this structure.
dwFlags
A set of bit flags that specify properties of the SoundSentry feature. The following bit-flag values are defined:
| Value | Meaning |
| SSF_AVAILABLE | If this flag is set, the SoundSentry feature is available. |
| SSF_SOUNDSENTRYON | If this flag is set, the SoundSentry feature is on. |
iFSTextEffect
Windows 95: Specifies the visual signal to present when a text-mode application generates a sound while running in a full-screen virtual machine. This member can be one of the following values:
| Value | Meaning |
| SSTF_BORDER | Flash the screen border (that is, the overscan area), which is unavailable on some displays. |
| SSTF_CHARS | Flash characters in the corner of the screen. |
| SSTF_DISPLAY | Flash the entire display. |
| SSTF_NONE | No visual signal. |
Windows NT: This member is reserved for future use. It must be set to zero.
iFSTextEffectMSec
Windows 95: Specifies the duration, in milliseconds, of the visual signal that is displayed when a full-screen, text-mode application generates a sound.
Wndows NT: This member is reserved for future use. It must be set to zero.
iFSTextEffectColorBits
Windows 95: Specifies the RGB value of the color to be used when displaying the visual signal shown when a full-screen, text-mode application generates a sound.
Windows NT: This member is reserved for future use. It must be set to zero.
iFSGrafEffect
Windows 95: Specifies the visual signal to present when a graphics-mode application generates a sound while running in a full-screen virtual machine. This member can be one of the following values:
| Value | Meaning |
| SSGF_DISPLAY | No visual signal. |
| SSGF_NONE | Flash the entire display. |
Windows NT: This member is reserved for future use. It must be set to zero.
iFSGrafEffectMSec
Windows 95: Specifies the duration, in milliseconds, of the visual signal that is displayed when a full-screen, graphics-mode application generates a sound.
Windows NT: This member is reserved for future use. It must be set to zero.
iFSGrafEffectColor
Windows 95: Specifies the RGB value of the color to be used when displaying the visual signal shown when a full-screen, graphics-mode application generates a sound.
Windows NT: This member is reserved for future use. It must be set to zero.
iWindowsEffect
Specifies the visual signal to display when a sound is generated by a Windows-based application or an MS-DOS application running in a window. This member can be one of the following values:
| Value | Meaning |
| SSWF_CUSTOM | Call the SoundSentryProc routine exported by the DLL specified by the iFSWindowsEffectDLL member. |
| SSWF_DISPLAY | Flash the entire display. |
| SSWF_NONE | No visual signal. |
| SSWF_TITLE | Flash the title bar of the active window. |
| SSWF_WINDOW | Flash the active window. |
iWindowsEffectMSec
Windows 95: 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.
Windows NT: This member is reserved for future use. It must be set to zero.
lpszWindowsEffectDLL
Points to the buffer that contains the name of the DLL that contains a SoundSentryProc callback function. The length of the name must not exceed the value of MAX_PATH. This member is NULL if no DLL is used. When retrieving information about the SoundSentry feature, the size of the buffer must be equal to, or larger than, the value of MAX_PATH.
iWindowsEffectOrdinal
This member is reserved for future use on both platforms. It must be set to zero.
Remarks
An application uses a SOUNDSENTRY structure when calling the SystemParametersInfo function with the wAction parameter set to SPI_GETSOUNDSENTRY or SPI_SETSOUNDSENTRY. When using SPI_GETSOUNDSENTRY, an application must specify the cbSize member of the SOUNDSENTRY structure; the SystemParametersInfo function fills the remaining members. An application must specify the cbSize, dwFlags, and iWindowsEffect members when using the SPI_SETSOUNDSENTRY value.
See Also