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Author: Joseph Emmanuel DL Dayo
e-mail: [email protected], [email protected]

This is the README.1ST file for DEX-OS 1.0 Beta

DESCRIPTION
===========
	DEX is an operating system specifically designed for educational and 
research use. The DEX Operating system allows for the dynamic 
reconfiguration and customization of various system services 
using concepts found in extensible operating systems. Additionally it 
aims to create an operating system design that would be easy to 
understand while having features that are common with today’s 
modern operating systems. Unlike other small operating systems, 
DEX-OS is powerful enough to support simple applications that 
require multithreading and file management. DEX-OS was developed in C 
and runs on PCs with 80386 processors or higher. The ultimate goal 
of this operating system is to achieve zero static inter-module calls, 
not even the scheduler or virtual memory manager is permanent 
and could be changed dynamically.

	In order to achieve this "plug-in" like capability, there is a 
need to generate generalizations about the interfaces of
the various operating system modules. Like for example, what features 
should a scheduler provide, or what methods or function calls should 
a virtual memory manager provide at a minimum. This part of the 
operating system is still under development, and only the scheduler and
the kernel malloc function is dynamic . Theses modules can be incorporated 
into the system through the means of Dynamic Link Libraries or 
shared objects, much like how a device driver would.



THE DISTRIBUTION
================

The DEX source distribution is divided into the following subdirectories:

/console		- Contains the modules that will handle virtual consoles
			  and the built-in text-mode shell
/devmgr		- Contains the device manager and the extension manager
/dexapi		- The DEX Application Programs Interface manager
/docs			- additional documentation
/filesystem		- Contains the filesystem drivers 
/grub		      - Contains the grub bootloader binaries
/hardware		- Contains device drivers for the various hardware found in 
			  an 80x86 system.
/iomgr		- Contains the IO manager module 
/memory		- Contains page management code and kernel malloc functions
/module		- Contains the module loader for various executables and 
			  libraries
/process		- Contains process management code
/startup		- Contains startup NASM assmebly files and
			  libraries
/stdlib		- Contains various standard C library functions
/vfs			- The Virtual File System (VFS) module
/vmm			- The Virtual Memory Management module

The main file is kernel32.c and some of the files are directly included in it.

INSTALLATION
=============
For the binary only release, the file kernel32.bin is multiboot compliant and
multiboot compliant bootloaders like GRUB can be used. Please refer to the GRUB
documentation for instructions on installing the GRUB bootloader on a FAT12
floppy disk.

See the user's manual for other details.

EDIT: kernel32.bin is now compressed using gzip therefore the file
should now be kernel32.bin.gz. The modification is relfected in the GRUB
configuration file.

COMPILING THE SOURCE CODE
=========================

For Windows/DOS
---------------
nasmw - netwide free assember 0.98 or greater
DJGPP gcc - The gcc compiler from DJ Delories
gzip - gzip compression utility

Simply invoke the make-kernel.bat batch file.

For Unix systems
----------------
The following utilities must be available
nasm - netwide free assembler 0.98 or greater
gcc - GNU C compiler and associated utilities
gzip - gzip compression utility
make - make file

There is an included makefile in the source, to compile just invoke
make. 

This will output kernel32.bin.gz which contains the compressed
dex-os kernel. This kernel can be booted by placing
the kernel32.bin.gz file in a floppy disk with grub installed
and modifying the menu.lst file to reflect the location of
kernel32.bin.gz (A menu.lst file is included in the source
package as well as the GRUB loaders in the GRUB folder)


POSSIBLE ERRORS
===============

Error: ld returns the following error message:
   		   
ld: PE operations on non PE file. 

Reason:
	   
The version of gcc or ld is not capable of producing BINARY
output formats. You must obtain the cross compiler capable
version of gcc and/or ld to be able to link the object files
together. Check using ld --help to determine the supported
output formats.

DJGPP is capable of producing BINARY formats out
of the box.