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#DEFINE SPI_GETSCREENSAVEACTIVE 16
#DEFINE SPI_SETSCREENSAVEACTIVE 17

#DEFINE SPI_GETBEEP 1
#DEFINE SPI_SETBEEP 2
#DEFINE SPI_GETMOUSE 3
#DEFINE SPI_SETMOUSE 4
#DEFINE SPI_GETBORDER 5
#DEFINE SPI_SETBORDER 6
#DEFINE SPI_GETKEYBOARDSPEED 10
#DEFINE SPI_SETKEYBOARDSPEED 11
#DEFINE SPI_LANGDRIVER 12
#DEFINE SPI_ICONHORIZONTALSPACING 13
#DEFINE SPI_GETSCREENSAVETIMEOUT 14
#DEFINE SPI_SETSCREENSAVETIMEOUT 15
#DEFINE SPI_GETSCREENSAVEACTIVE 16
#DEFINE SPI_SETSCREENSAVEACTIVE 17
#DEFINE SPI_GETGRIDGRANULARITY 18
#DEFINE SPI_SETGRIDGRANULARITY 19
#DEFINE SPI_SETDESKWALLPAPER 20
#DEFINE SPI_SETDESKPATTERN 21
#DEFINE SPI_GETKEYBOARDDELAY 22
#DEFINE SPI_SETKEYBOARDDELAY 23
#DEFINE SPI_ICONVERTICALSPACING 24
#DEFINE SPI_GETICONTITLEWRAP 25
#DEFINE SPI_SETICONTITLEWRAP 26
#DEFINE SPI_GETMENUDROPALIGNMENT 27
#DEFINE SPI_SETMENUDROPALIGNMENT 28
#DEFINE SPI_SETDOUBLECLKWIDTH 29
#DEFINE SPI_SETDOUBLECLKHEIGHT 30
#DEFINE SPI_GETICONTITLELOGFONT 31
#DEFINE SPI_SETDOUBLECLICKTIME 32
#DEFINE SPI_SETMOUSEBUTTONSWAP 33
#DEFINE SPI_SETICONTITLELOGFONT 34
#DEFINE SPI_GETFASTTASKSWITCH 35
#DEFINE SPI_SETFASTTASKSWITCH 36

#DEFINE SPIF_SENDWININICHANGE 2
#DEFINE SPIF_UPDATEINIFILE 1

*-- Get the current setting
lnRetValue = 0
? SystemParametersInfo( SPI_GETSCREENSAVEACTIVE, 0, @lnRetValue, 0 )

*-- Toggle the value
? SystemParametersInfo( SPI_SETSCREENSAVEACTIVE, IIF( m.lnRetValue == 0, 1, 0 ), @lnRetValue, 0 )

RETURN

*****************************
FUNCTION SystemParametersInfo( tnAction, tlParam, tnRetValue, tnWinIni )
*****************************

DECLARE SHORT SystemParametersInfo IN WIN32API AS SystemParameters_A ;
INTEGER uiAction,;
INTEGER uiParam, ;
INTEGER @pvParam,;
INTEGER fWinIni

RETURN( (SystemParametersInfo_A( tcAction, tlParam, @tnRetValue, tnWinIni) != 0) )