OSDev.org

I want to get started with os development, have created all the files from Bare Bones tutorial, everything compiles and links, but i can't create an disk image.
I have read the OSDev wiki article about mkisofs, but i still can't get it.
I am using Windows, with CDRTools installed and added to PATH.
Running the mkisofs command works.
My project structure looks like this:

>OS
--->img
------>boot
--------->grub
------------>stage2_eltorito
------------>menu.lst
------>system
--------->kernel.elf
--->kernel.c
--->boot.asm
---> builder.bat (my own script that builds the project, haven't learnt makefile yet)
--->all object files...
In the builder.bat file I added mkisofs -b iso/boot/grub/stage2_eltorito -no-emul-boot -boot-load-size 4 -boot-info-table -o bootcd.iso iso , but it says:
Setting input charset to 'UTF-8' from local
mkisofs: Uh oh, i cant find the boot image iso/boot/stage2_eltorito inside the target tree

Plz explain me how to use this command.

Did you read this? http://wiki.osdev.org/Bootable_El-Torit ... boot_image

StartOS wrote:

Code: Select all

--->img
------>boot
--------->grub
------------>stage2_eltorito

Code: Select all

mkisofs -b iso/boot/grub/stage2_eltorito -no-emul-boot -boot-load-size 4 -boot-info-table -o bootcd.iso iso

Code: Select all

mkisofs: Uh oh, i cant find the boot image iso/boot/stage2_eltorito inside the target tree

Use the correct path.

Thanks for the help.
The iso mounts correctly in VirtualBox and GRUB loads, however I still get a problem.
GRUB loads an command line instead of my os.
Whats wrong???
The menu.lst file looks like this:
default 0

title StartOS
kernel /boot/kernel.elf

StartOS wrote:Thanks for the help.
The iso mounts correctly in VirtualBox and GRUB loads, however I still get a problem.
GRUB loads an command line instead of my os.
Whats wrong???
The menu.lst file looks like this:
default 0

title StartOS
kernel /boot/kernel.elf

I think it does that if it can't find your grub.cfg

I use GRUB version 0.95.
I think there is no grub.cfg needed

What's in your menu.lst?

menu.lst should contain the following:

OSDev Wiki wrote: menuentry "OS" {
multiboot /boot/system/kernel.elf
}

Got it right by:
Placing kernel.elf in /boot
Changing menu.lst
Using other ARGV's with mkisofs
But now GRUB says:
Error 13: Invalid or unsupported file format
What??? GRUB does not support multiboot ELF files???

StartOS wrote:Error 13: Invalid or unsupported file format

Show us your linker script and/or listen to the wiki .

I use the linker script provided in the BareBones tutorial and the bootstarp assembly in Bare Bones with nasm

We can assume that you have created a 32-bit gcc cross-compiler which you are using for this project?

Nope I don't have an cross compiler.
I thought it would be possible with standard MinGW.
I also use my computer to develop system dependent software and don't want to install another compiler for os development.
What extra ARGVs should I add to make it work.
I use the commands from BareBones, but with gcc instaed of i686-elf-gcc.

StartOS wrote:Nope I don't have an cross compiler.
I thought it would be possible with standard MinGW.
I also use my computer to develop system dependent software and don't want to install another compiler for os development.
What extra ARGVs should I add to make it work.
I use the commands from BareBones, but with gcc instaed of i686-elf-gcc.

Bad, bad ! You must make a cross-compiler. You have been previously warned (in BareBones) that this could create problems, and it did! Are you developing in a 32-bit machine, or a 64-bit machine? If you're using 64-bits, that's part of the issue. Also, MinGW sounds me like you're generating PEs instead of ELFs with your distributed compiler. GRUB will never recognize this. No flags will fix this, you need a cross-compiler targeted for i686-elf! A simple test? Write a Hello World and compile it with your standard gcc. Then try to run it in full Windows. If it works, you're the wrong way...

StartOS wrote:Nope I don't have an cross compiler.
I thought it would be possible with standard MinGW.

Well, the good news is that you have now determined what the problem is. If you are going to follow a tutorial you ought to (at least to start with) follow the tutorial.