GEM :: Desktop Environments
Open Source :: Operating Systems
FreeDOS :: DOS

Dissecting DOS: A Code-Level Look at the DOS Operating System - By Michael Podanoffsky; Addison-Wesley, 1994, ISBN 020162687X, has CD-ROM. Explores DOS structure, function from programmer view, overall architecture, command structure, code-level details of vital actions. [Amazon.com]
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RxDOS - Fast industrial strength DOS compatible RTOS, supports huge disk drives, FAT32 volumes, Windows 95/98 long filenames, coded in Assembly, used mostly in embedded systems and similar uses. [Open Source, GPL]
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RxDOS Downloads - Several Zip format files: readme, bootable MASM files: RxDOS sources, binaries. Another OS: RTX, fast, multithreaded for DOS in C.

Samsung Computer Division: Products: RxDOS Series - Instructions on making a bootable RxDOS floppy, and these files: disk image, Zip files with executable binaries (old, newest), GPL license. Useful for updating BIOS or MICOM.
Meta Description: [ Samsung support for software drivers for notebook and laptop computer products notebooks laptops ]