[syslinux] vesamenu back to text before booting

[Ady]

> On Wed, Dec 3, 2014 at 1:30 PM, Geert Stappers <stappers at stappers.nl> wrote:
> > H. Peter Anvin wrote:
> > } Thorsten Glaser wrote:
> > } } When I have an environment that uses vesamenu, for example on PXE,
> > } } how do I configure it so that, for some of the menu entries, it
> > } } switches back to the text mode (03h) before handing off to the next
> > } } bootloader / kernel?
> > }
> > } depends on the image type.  We should reset for an NBP though.
> > }
> >
> > How to keep "state" during the reset?
> 
> Where should the decision to reset the screen lie?  Should it be
> forced by the core/ldlinux or perhaps allow the menu/user to dictate
> if it's reset?  I agree the default should be to reset the screen but
> at the same time, I could see use cases for not clearing the screen
> (including with chain.c32 and pxechn.c32).
> 
> -- 
> -Gene
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This is starting to be confusing to me.

Why should this depend on which kernel/module (type) is launched?

Are we still talking about vesamenu.c32 only?

The MENU CLEAR directive (and [Ctrl+L]) is supposed to move the cursor 
to home and clear the text on the screen before launching the selected 
menu entry, while leaving the background (image) for as long as the 
screen remains in graphics mode. In Syslinux 6.xx, MENU CLEAR is 
already failing to complete its goal (it only moves the cursor to home, 
so this is a bug).

Perhaps there should be a new MENU-type directive, so to force the 
screen to text mode (as opposed to leaving it in graphics mode for as 
long as it can be)? Perhaps this could also be useful when exiting a 
vesamenu to Syslinux CLI?

FWIW, the DISPLAY files already have the possibility of adding ASCII 25 
(force text mode) and part of the ASCII 16-23 (select output mode). 
These are only useful after exiting the DISPLAY file, but perhaps there 
is some similar logic to be applied to vesamenu.c32 (new directive?).

Or maybe this is too-much a complication (considering the current 
resources available for development) and the answer should be "just use 
menu.c32 and/or CLI instead of (or in addition to) vesamenu"?

I hope I am not introducing too much noise in the discussion.

Regards,
Ady.