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[CBoot : boot your P.C. programmaticly ] | ||
Environment: Win 95/98 VC6 SP1 CBoot is a very simple class : if provides 4 basic function to perform various types
of computer boot , OS boot etc.
The boot process works as follows : if an application wishes to boot :
it (you - the programmer) calls ExitWindowsEx(UINT nFlags ,0); with desired flags.
this function sends WM_QUERYENDSESSION message to all aplications (top level windows)
with 0 in WPARAM (reserved) and flags of boot in LPARAM.
Every application may (should) override this function and do his own set of end-session
activities (such as destroying heap , relase all memory, save state).
If an application allows its own termination it return TRUE. (This is also the default behaviour in DefWindowProc)
but if it doesn't : it return FALSE . If doing that termination is canceled (an Exit windows dialog is being
shown by window). All this is true whenever ExitWindowsEx is conditional : it wont continue if one
application disapprove . Adding EWX_FORCE to flags forces boot and application responces aren't checked.
You understand what each one is doing from the name :
static BOOL Logoff(BOOL bEmergency=FALSE,BOOL bShowWarning=FALSE);
static BOOL Poweroff(BOOL bEmergency=FALSE,BOOL bShowWarning=FALSE);
static BOOL Reboot(BOOL bEmergency=FALSE,BOOL bShowWarning=FALSE);
static BOOL Shutdown(BOOL bEmergency=FALSE,BOOL bShowWarning=FALSE);
since the functions are static you don't have to instantiate the class:
you simply call CBoot::LogOff(); to log-off with default behaveiour.
The function where all job happens is a static one : CBoot::Boot .This function calls the API : ExitWindowEx.
All these functions include 2 additional parameters that get default
values : BOOL bEmergency causes the function to add EWX_FORCE to ExitWindowsEx
flags to force boot : even if the top level window doen't respond : TRUE;
but you may loose unsaved information.
BOOL bShowWarning=TRUE adds a dialog (of type MessageBox) of warning , the dialog is located in Warning function.
You may change this function to modify the MB_YESNO|MB_ICONWARNING type of MessageBox.
