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Hello again i compile code:
gcc -c kernel.c
ld kernel.o -o kernel.sys -oformat binary -Ttext 0x100000

But GRUB doesnt load it, it should be an elf format how i should input eld definition into my code?

You seem to be linking to binary - if so, you need to use the aout kludge, see [1].
I recommend you use a linker script that links to ELF, see [1] again.

1. http://osdev.berlios.de/grub.html