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(multiboot.info)OS image format

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OS image format
===============

   An OS image may be an ordinary 32-bit executable file in the standard
format for that particular operating system, except that it may be
linked at a non-default load address to avoid loading on top of the
PC's I/O region or other reserved areas, and of course it should not
use shared libraries or other fancy features.

   An OS image must contain an additional header called "Multiboot
header", besides the headers of the format used by the OS image. The
Multiboot header must be contained completely within the first 8192
bytes of the OS image, and must be longword (32-bit) aligned. In
general, it should come _as early as possible_, and may be embedded in
the beginning of the text segment after the _real_ executable header.

Header layout

The layout of Multiboot header

Header magic fields

The magic fields of Multiboot header

Header address fields

Header graphics fields