grub2 miscelanea questions (2/2)

grub2 miscelanea questions (2/2)

[adrian15]

Comes from grub2 miscelanea questions (1/2)


14) help linux
=================
Usage: linux FILE [ARGS...]
Load a linux kernel.

I think that a message telling the user that the ARGS are arguments for
the linux kernel instead of arguments for the grub's linux command would
be a good idea.


15) lsmod
==============

As long as I am unable to run a pager can anyone tell me what the three
columns mean?

cat	1	normal,gzio
gzio	6	
boot 	1	normal

16) help play
===================

Usage: play FILE
Play a tune

What is the FILE format? Is it an AIFF, an AU, a WAV, or is it an ASCII
file that has tones?

I should not go to the source code for knowing it.

17) play ideas
==================
It seems a rather complicated file... is there any utility for creating
it from grub2 or is it standard file that I do not know of?

Maybe it should have a --loop and -l argument. So that if no key is
pressed the file is played again.

Another --delay -d argument can be useful for determining the delay
period between one reproduction and another.

18) source, . , and configfile
=================================

If both source and '.' commands say that:
Load another config file without changing context.
Then the configfile command should say:
Load another config file (with a new context)
instead of saying:
Load another config file.

19) rescue and exit failure on qemu
==============================
I think that booting from my computer does not give this error.
If I boot from QEMU and type:

grub> rescue
and then :
grub rescue> exit

it says: FATAL: INT18: BOOT FAILURE

20) grub rescue help
========================

help : Types the commands and a minimal explanation: OK
help any_command : Types the commands and a minimal explanation: NOT OK
help not_a_command : Types the commands and a minimal explanation: NOT OK

21) grub rescue exit help
===========================
When you are in grub rescue mode and you type help the exit line it's
the following one:

exit	exit from GRUB

Should it not prompt ?

exit	exit from GRUB rescue

22) copyright message missing
================================
Why isn't there (when Grub is running) any message about the GRUB
Copyright and the GPL license and that you should have received and this
and that?

Is it a memory problem? (In grub legacy there was not any message like
this either)

Maybe we should implement an 'about' command and run it when booting :) ?

23) set read only variables
==============================
unset prefix lets me "delete" the prefix variable.
unset root does not let me the "root" variable.

I remember that bash has an option to set read only variables.
Maybe the root variable is a read only variable?

24) 'Command' commands
==========================
Is there any special reason why the
rescue, set, unset, export, insmod, rmmod, lsmod commands are in a
single file called: normal/command.c
instead of being in separate files in commands/ folder ?




adrian15

Re: grub2 miscelanea questions (2/2)

[Marco Gerards]

adrian15 <adrian15@raulete.net> writes:

> Comes from grub2 miscelanea questions (1/2)
>
>
> 14) help linux
> =================
> Usage: linux FILE [ARGS...]
> Load a linux kernel.
>
> I think that a message telling the user that the ARGS are arguments for
> the linux kernel instead of arguments for the grub's linux command would
> be a good idea.

The loader itself also has arguments.  Perhaps the documentation can
be improved.

> 15) lsmod
> ==============
>
> As long as I am unable to run a pager can anyone tell me what the three
> columns mean?
>
> cat	1	normal,gzio
> gzio	6	
> boot 	1	normal

The number of references to the command and the modules it refers to

> 16) help play
> ===================
>
> Usage: play FILE
> Play a tune
>
> What is the FILE format? Is it an AIFF, an AU, a WAV, or is it an ASCII
> file that has tones?
>
> I should not go to the source code for knowing it.

ASCII IIRC.  Vicent has some tunes somewhere :-).  Perhaps they are
already included somewhere.

[...]

> 18) source, . , and configfile
> =================================
>
> If both source and '.' commands say that:
> Load another config file without changing context.
> Then the configfile command should say:
> Load another config file (with a new context)
> instead of saying:
> Load another config file.

Right, they are not the same.

> 19) rescue and exit failure on qemu
> ==============================
> I think that booting from my computer does not give this error.
> If I boot from QEMU and type:
>
> grub> rescue
> and then :
> grub rescue> exit
>
> it says: FATAL: INT18: BOOT FAILURE

Weird.  Can you debug this?

> 20) grub rescue help
> ========================
>
> help : Types the commands and a minimal explanation: OK
> help any_command : Types the commands and a minimal explanation: NOT OK
> help not_a_command : Types the commands and a minimal explanation: NOT OK

huh?

> 21) grub rescue exit help
> ===========================
> When you are in grub rescue mode and you type help the exit line it's
> the following one:
>
> exit	exit from GRUB
>
> Should it not prompt ?
>
> exit	exit from GRUB rescue

The exit command terminates GRUB and continues the boot process, IIRC.

> 22) copyright message missing
> ================================
> Why isn't there (when Grub is running) any message about the GRUB
> Copyright and the GPL license and that you should have received and this
> and that?

Why should there be such message?

> Is it a memory problem? (In grub legacy there was not any message like
> this either)

No, memory is not an issue.

> Maybe we should implement an 'about' command and run it when booting :) ?

Perhaps, but I don't see the added value.

> 23) set read only variables
> ==============================
> unset prefix lets me "delete" the prefix variable.
> unset root does not let me the "root" variable.
>
> I remember that bash has an option to set read only variables.
> Maybe the root variable is a read only variable?

You can easily modify the code.  But I do not like making such
variables read-only.

> 24) 'Command' commands
> ==========================
> Is there any special reason why the
> rescue, set, unset, export, insmod, rmmod, lsmod commands are in a
> single file called: normal/command.c
> instead of being in separate files in commands/ folder ?

Yes, there is.  First of all the commands are quite trivial.  Besides
that, these commands are really the core of GRUB 2.  The same commands
are hardcoded into rescue mode as well.

--
Marco

Re: grub2 miscelanea questions (2/2)

[Robert Millan]

On Sat, Jun 09, 2007 at 09:35:10AM +0200, adrian15 wrote:
> 23) set read only variables
> ==============================
> unset prefix lets me "delete" the prefix variable.
> unset root does not let me the "root" variable.
> 
> I remember that bash has an option to set read only variables.
> Maybe the root variable is a read only variable?

I have manually overriden both of these some times.  It's useful for debugging
(i.e. not completely breaking your system when prefix wasn't set properly).

-- 
Robert Millan

My spam trap is honeypot@aybabtu.com.  Note: this address is only intended
for spam harvesters.  Writing to it will get you added to my black list.

Re: grub2 miscelanea questions (2/2)

[adrian15]

>> 19) rescue and exit failure on qemu
>> ==============================
>> I think that booting from my computer does not give this error.
>> If I boot from QEMU and type:
>>
>> grub> rescue
>> and then :
>> grub rescue> exit
>>
>> it says: FATAL: INT18: BOOT FAILURE
> 
> Weird.  Can you debug this?

I've checked this again.
If I do this booting from my pc I get the grub2 floppy booting again.
If I do this from qemu the FATAL: INT18: BOOT FAILURE appears again.
I would bet that it is a qemu bios's lack of the 18 interruption.
>> 20) grub rescue help
>> ========================
>>
>> help : Types the commands and a minimal explanation: OK
>> help any_command : Types the commands and a minimal explanation: NOT OK
>> help not_a_command : Types the commands and a minimal explanation: NOT OK
> 
> huh?

You boot grub2 and you see
grub>
you type rescue and you see
grub rescue>
and now what it is funny that if you type the help command, an space,
and whatever you want to write it always shows all the commands help.

It may confuse some users as "Grub is not working".

> 
>> 21) grub rescue exit help
>> ===========================
>> When you are in grub rescue mode and you type help the exit line it's
>> the following one:
>>
>> exit	exit from GRUB
>>
>> Should it not prompt ?
>>
>> exit	exit from GRUB rescue
> 
> The exit command terminates GRUB and continues the boot process, IIRC.
You are right. Exit from GRUB is right, then.

> 
>> 22) copyright message missing
>> ================================
>> Why isn't there (when Grub is running) any message about the GRUB
>> Copyright and the GPL license and that you should have received and this
>> and that?
> 
> Why should there be such message?
This comes from GPL 2:

If the program is interactive, make it output a short notice like this
when it starts in an interactive mode:

     Gnomovision version 69, Copyright (C) year  name of author
     Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type
`show w'.
     This is free software, and you are welcome to redistribute it
     under certain conditions; type `show c' for details.

>> Maybe we should implement an 'about' command and run it when booting :) ?
> Perhaps, but I don't see the added value.
See above about the GPL.
> 
>> 23) set read only variables
>> ==============================
>> unset prefix lets me "delete" the prefix variable.
>> unset root does not let me the "root" variable.
>>
>> I remember that bash has an option to set read only variables.
>> Maybe the root variable is a read only variable?
> 
> You can easily modify the code.  But I do not like making such
> variables read-only.

I did not want to make any variable read only. I only wanted to make you
know that the "root" variable was actually a read only variable because
there is no way to delete (unset) it. It always comes to live again.

Is it a normal thing?

adrian15