秋梦无痕

在SMTH看到问题和解决方案，总结如下：

#include <windows.h>

int APIENTRY WinMain(HINSTANCE,HINSTANCE,LPSTR,int) {
BOOL bActive = FALSE;
//判断当前是否已经设置屏幕保护，根据返回的参数判断
::SystemParametersInfo(SPI_GETSCREENSAVEACTIVE,0,&bActive,0);

if(bActive) {
//取消屏幕保护
::SystemParametersInfo(SPI_SETSCREENSAVEACTIVE,FALSE,0,0);
}

//关闭显示器
SendMessage(HWND_BROADCAST, WM_SYSCOMMAND, SC_MONITORPOWER, 2);
Sleep(120000);
//打开显示器
SendMessage(HWND_BROADCAST, WM_SYSCOMMAND, SC_MONITORPOWER, -1);

if(bActive) {
//启用屏幕保护
::SystemParametersInfo(SPI_SETSCREENSAVEACTIVE,TRUE,0,0);
}
return 0;
}