Tiny Core Linux

Tiny Core Base => TCB Talk => Topic started by: b1ackmai1er on January 20, 2011, 06:34:45 AM

Title: default boot commands
Post by: b1ackmai1er on January 20, 2011, 06:34:45 AM

Hi,

For quick remaster with custom boot commands how about using the boot label to store the boot command.

TC could check the label for a command and run it automatically after the boot command line times out.

regards b1ackmai1er

Title: Re: default boot commands
Post by: beerstein on January 20, 2011, 08:03:22 AM

hi, can you explain this a bit more - what is the boot label? where is it stored?
where are the folders and files?

Thank you so much

Title: Re: default boot commands
Post by: curaga on January 20, 2011, 10:20:38 AM

The label is not passed to TC, it's handled entirely by the bootloader. But if you want to have different bootcode sets, using labels is a good way to do that.

Edit: or did you mean alternative init scripts? The kernel has bootcode(s) for that.

Title: Re: default boot commands
Post by: beerstein on January 20, 2011, 12:03:31 PM

Quote from: curaga on January 20, 2011, 10:20:38 AM

The label is not passed to TC, it's handled entirely by the bootloader. But if you want to have different bootcode sets, using labels is a good way to do that.

Edit: or did you mean alternative init scripts? The kernel has bootcode(s) for that.

Edit: Thank you for the response Sorry I do not understand what you mean
When I want to remaster, I would like to have the boot code (f. i. wait usb or so) in my
remastered iso. So where do I insert that boot code before remastering?

Title: Re: default boot commands
Post by: curaga on January 20, 2011, 12:41:45 PM

In the bootloader config file for the cd, which would be boot/isolinux/isolinux.cfg.

Title: Re: default boot commands
Post by: b1ackmai1er on January 21, 2011, 08:26:53 AM

A cdrom can have 32 character disk label which can be displayed using:

dd if=/dev/sr0 bs=1 skip=32808 count=32


What I am suggesting that when the system boots and waits for the optional boot command, that on expiration of that timeout it reads the text from the label field and uses this as the boot command.
 
The advantage of this is that burning tools such as imgburn can easily change the label text without having to do anything else with the iso.

So I could download latest TC iso. Start imageburn, change label to say "VGA=775" and then immediately burn iso to disk. Now disk will boot and use this boot command if another is not entered.

If this is outside scope of TC I would be interested in suggesting this to the developers of the boot code. Could anyone tell me who that is ?

Thanks

Title: Re: default boot commands
Post by: gerald_clark on January 21, 2011, 10:43:15 AM

What would be the point.
The boot loader can have a default boot entry. It doesn't need to read a disk label to pick one.

Title: Re: default boot commands
Post by: tinypoodle on January 21, 2011, 01:17:50 PM

Sounds more like a case of what rdev had implemented within the kernel since a long time - not even sure if that would still be supported as of now:
http://linux.die.net/man/8/rdev

Anyway, if you really want to contact the developers of syslinux (incl. isolinux):
http://syslinux.zytor.com/wiki/index.php/Contact

Title: Re: default boot commands
Post by: b1ackmai1er on January 21, 2011, 09:43:18 PM

@tinypoodle

Thanks I will suggest this to the syslinux developers.

I know this can be achieved in other ways but all the other solutions require getting down to file level whereas the idea behind this is that you do not even have to boot the disk to set this up. Changing the default boot instruction becomes a point and click operation.