This book provides detailed and comprehensive comments andexplanations on all source code of the early Linux-0.12 kernel,aiming to enable readers to gain a comprehensive and profoundunderstanding of the working mechanism of Linux in a shortestpossible time and to lay a solid foundation for further study ofmodern Linux systems. Although the version of the analysis is

very low, the kernel has been able to compile and run, and it alreadyincludes the essence of the working principle of Linux.

The book first briefly introduced the development history of theLinux kernel, explained the main differences between the variouskernel versions and improvements, and gave the reasons forchoosing the 0.12 kernel source code as the study object.

Then it gives the basic knowledge needed to read the source code,outlines the hardware structure of the PC running the Linuxsystem, the assembly language used by the kernel, the extendsof C language, and focuses on the 80X86 processor in protectedmode.

Then weintroduced the kernel code overview, given thekernel source directory tree structure, and according to theorganizational structure of all kernel, programs and files aredescribed in detail. In order to deepen the reader's understandingof the working principle of the kernel, the last chapter gives anumber of related operational debugging tests. All relevantinformation in the book can be downloaded from the websitewww.oldlinux.org.

This book suits as the assistant and practical teaching materialof university computer major student study operating systemcourse, also suitable for self-study reference book of Linux loversas learning kernel operating principle, also can be used as thereference book that the general technical personnel developsthe embedded system.

Table of Contents

1. Overview 

2. Microcomputer Structure

2. Kernel Programming Language and Environment

4. 80x86 Protection Mode and Its Programming

5. Linux Kernel Architecture

6. Booting System

7. Initialization Program (Init)

8. Kernel Code (Kernel)

9. Block Device Driver

10. Character Device Driver

11. Math Coprocessor (Math)

12. File System (FS)

13. Memory Management (MM)

14. Header Files (Include)

15. Library Files (Lib)

16. Building Kernel (Tools)

17. Experimental Environment Settings and Usage.