《现代操作系统》小注
中国古人中颇有些喜欢作注的人，如晋朝裴松之为《三国志》做注几乎被引为正史，北魏郦道元的《水经注》在中学课本上折磨得广大学子摇摇欲坠，明清兴起的以《红楼梦》为代表小说注评更加繁盛，外国做笔记的那个费马大定理更是被传为佳话，其实说到底这些注就是于古人的读书笔记，或有所思想、或与作者共鸣，或考证有得，咸列而陈之。所以我们读书要做笔记，笔记很重要。
所以这里就是我读《现代操作系统》的读书笔记，称之为注。然而对于此伟大的书，称之为注则颇有僭越之嫌，故称之为小注，想来也是合宜的。
《现代操作系统》是一本包罗万象的书，其作者有一堆，已经无法概括其伟大的头衔，窃以为其伟大的成就应该至少包含一项：不允许Linus改自己的代码，间接逼着Linus写出Linux的内核。
这本书内容紧随技术潮流，略翻一翻，居然有Windows8、Android、Linux的内容，相比古老晦涩的《Linux Device Driver》3th,《Linux Kernel Development》3th等已经太监许久的Linux圣经一般的书，这种与时俱进无疑是珍贵的，相对于前面的版本，大幅动刀，颇有已故金庸先生的严谨态度，简直堪比曹雪芹的“披阅十载,增删五次“的治学精神。另外书中不少作者的官方吐槽， 也颇引人莞尔。此书高屋建瓴，着眼大局，而又能小处入手，我刚开始看，书中的阐述有的颇为艰深，需要翻书上网查资料，故而这里做小注的时候就会引用颇多的资料名以及书名，希望引用不会引起侵权，毕竟广大中国程序员大部分都是“法盲”（如技术无罪的王欣），如果侵权，联系我，别告我，别搞我！
我这边看书的时候主要手边备有：
《现代操作系统》英文版第4版，中文版第3版
《Linux内核设计与实现》 第3版
《Linux设备驱动程序》第3版
《Linux 设备驱动程序ARM开发详解-基于最新的Linux4.0内核》宋宝华
《程序员的自我修养--链接、装载与库》俞甲子、石凡、潘爱民著
第一章：引论
1.0 Go learn that!
Can you imagine geting a job maintaining an operationg system and on the first day having your boos bring you to a bookcase with the code and say:"Go learn that."And this is only for the part that runs in the kernel.
- 我也不知道周星驰版本的《鹿鼎记》中，陈松仁饰演的陈近南送给周星驰饰演的韦小宝一本《绝世武功目录》的场景是不是取自于这里，也许是两代大师的跨领域的心有灵犀？但是很明显，操作系统的源码数量绝对超过了电影中那一垛秘笈。因为Windows的源码> 70million lines。
1.2 History of operating systems
1.2.3 第三代计算机的时代
...Since in those days people knew how to write small , efficient programs, a skill that has subsequently been completely lost.
- 官方吐槽现在的软件工程师。
The desire of a free production (as opposed to educational) version of MINIX led a Finnish student, Linus Torvalds, to write Linux.
- 作者和Linus的渊源。
1.2.4 第四代计算机的时代
... Since Intel did not think that disk-based microcomputers had much of a future, When Kidall asked for the rights to CP/M, Intel granted his request. Kidal then formed a company , Digital Research, to further develop and sell CP/M. In 1977, Digital Research reworte CP/M to make it suitable for running on many microcomputers, ....., make CP/M dominate the world of microcomputing for 5 years.
- Intel的短见，成就了Kidal和CP/M。
...1980 IBM designed the IBM PC and looked around for software to run it. People from IBM contacted Bill Gates to lincense his BASIC interpreter.They also asked him if he knew of an operating system to run on the PC. Gates suggested that IBM contact Digital Research, then the world's dominant operating systems company. Making what was surely the worest bussiness decision in recorded history, Kidall refused to meet with IBM, sending a subordinate instead. To make matters even worse, his lawer even refused to sign IBM'S nondisclosure agreement covering the not-yet-announced PC.
When IBM came back, Gates realized that a local computer manufacturer Seattle Computer Products, had a suitable operating system, DOS(Disk Operating System), He approached them and asked to buy it (allegedly for $75000), which they readily accepted. Gates then offered IBM a DOS/BASIC package, which IBM accepted....... After all this transpired, Kidall died suddenly and expectedly from caused that have not been fully disclosed.
- 致命错误犯一个就已经很可怕了，Kidall连着犯了两个,傲慢是会传染的。含着金钥匙出生的伟大商人，比尔盖茨，抓住机会，一竹竿捅翻了Kidal和他的CP/M。接着Kidall 就突然离世，可能黄泉抱憾。
- 看见常见的NDA的全拼了么：nondisclosure agreement？
