On Mon, 17 Aug 1998, R. Brock Lynn wrote:
> Glynn Clements wrote:
> >
> > James wrote:
> > > i want to make a text-based screensaver that has a block that moves
> > > around the screen (saw it once on some ancient netware server), i could
> > > write the program, but how would i make it run instead of the builtin
> > > screen blanker?
> >
> > I suspect that you'll need to modify the kernel; there doesn't seem to
> > be any simple way to determine when the screen saver should be
> > activated.
>
> Not that this is directed at you personally Glynn, but rather it's directed at
> your idea: THAT'S BULLSHIT MAN, BULL SHIT!!!
Not exactly.
The kernel implements its own screen saver and that is the screen blanking or
vesa/apm blanking. I know that vesa/apm blanking is runtime configurable, but I don't
think the regular screen blanking (erasing of all characters on screen) is. So unless
you don't want your text mode screensaver to be active for awhile until the kernel
screen
blanker kicks in, you'll need to do something with the kernel.
I dont know if this got into the kernel or not, but at one time I remember seeing a
small
patch that would send kerneld a ipc message when it wanted a screensaver to activate.
Kerneld
would then response by invoking the userspace program.
/dev/random garbage is generated by what the kernel developers thought of as random
events. The
timing between keystrokes and interrupts (mouse) are used as a seed. While it does
become active
and spew out garbage when you hit the keyboard and mouse, I'm pretty sure thats not
the only events
that drive it. Besides, if you have a daemon process in the background with
/dev/random open, I
am not sure if another process can open it.
~Jesse Off
