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#1 pscEx

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Posted 09 January 2011 - 06:29 PM

"Standard" ISOs can have the bootfix.bin file.

That causes, that the CD as primary boot device does not automatically boot, but asks:
"Hit any key to boot from CD"

Is there a similar functionality available in Grub4dos?

Peter

#2 sbaeder

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Posted 09 January 2011 - 08:35 PM

"Standard" ISOs can have the bootfix.bin file.

That causes, that the CD as primary boot device does not automatically boot, but asks:
"Hit any key to boot from CD"

Is there a similar functionality available in Grub4dos?

Peter

Not exactly, but there is the ability to specify a default action and a "timeout"...But you probably knew that already... :huh:

But, using that, it would be more that if they didn't hit a key in the timeout period, it would go do the default, which could be to go to the hard disk and do a "normal" boot...But, if they did press a key, It would go to a menu of some sort...Not exactly the same, but close...

What you're looking for is something that has a default, but something like a second "default" if all they did was press any character...Interesting challenge...

Scott

#3 pscEx

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Posted 10 January 2011 - 02:26 PM

Thanks, Sbaeder, but my intention is "one level lower"

I'm looking for a functionality like this:
Before Grub4dos boots from a device, it asks whether to boot or not.
If the answer is "No", boot device is changed to the next device in the BIOS boot order list.
(And maybe the MBR causes boot with M$)

EDIT: Now I understand your suggestion completelly! (Sorry for the delay) Maybe I can reach what i'm intenting ...

Peter

#4 COD11

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Posted 18 January 2011 - 07:06 PM

...
I'm looking for a functionality like this:
Before Grub4dos boots from a device, it asks whether to boot or not.
If the answer is "No", boot device is changed to the next device in the BIOS boot order list.
(And maybe the MBR causes boot with M$)
...


I recently implemented such a function in my updated "minimalist" Master Boot Record (MBR) for Grub4Dos ( unpublished yet, but see here for the older version and its prerequisites ). I just had to "play" a little bit with BIOS interrupts. See spoiler.

"To Boot or Not to Boot: That is the option!" (based loosely on W.Shakespeare)
Spoiler

Hints:

1. This code is an excerpt of a MBR, NOT a working MBR code.

2. It does NOT run within a DOS window under Windows, because access to BIOS interrupts is restricted.

3. If you use qemu/MobaLiveCD, you have to increase delay value of INT 15h to CX=0040h / DX=0000h, otherwise you get no chance to press a key. INT 18h is of course not working, but you get an appropriate fault message.

4. If your UFD is recognized as HDD /(hd0,0) by the BIOS, the built-in HDD most often does NOT appear in BIOS boot order anymore. If there is no other second bootable device, you will get a BIOS fault message and may restart with Ctrl+Alt+Del, if timeout is reached. This problem does not occur, if your UFD is recognized as USB ZIP or USB LS120 drive by the BIOS.

Edited by COD11, 18 January 2011 - 07:12 PM.





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