UNIX/Linux Operating System Haiyong Zheng http://vision.ouc.edu.cn/~zhenghaiyong

Contents History and Hackers UNIX-like Structure Bourne Again SHell

Contents History and Hackers UNIX-like Structure Bourne Again SHell

UNIX Since 1969

Since 1965 GE-645 + => DEC PDP-7 Since 1969 Since 1971 MULTiplexed Information and Computing Service General-Purpose Time-Sharing Multi-User + => Batch Processing Space Travel DEC PDP-7 Since 1969 UNiplexed Information and Computing Service Since 1971 DEC PDP-11/24 UNIX Memory: 12KB 2 Space Travel: 12KB Memory: 24KB Harddisk: 500KB Since 1973 Assembly 3rd Kernel C July 1974 5th UNIX EduOnly

Minix=>Freax=>Linux 4.X BSD System IV System V Since 1978 1992 POSIX Linux GNU Minix=>Freax=>Linux GNU’s Not Unix Since 1991 Since 1984 http://www.kernel.org http://www.gnu.org http://www.fsf.org

http://zh.wikipedia.org/wiki/UNIX

480 distros

Contents History and Hackers UNIX-like Structure Bourne Again SHell

Version 7 UNIX PDP11 Filesystem Layout

Contents History and Hackers UNIX-like Structure Bourne Again SHell

GNU/Linux Bash vim ssh RegEx grep sed awk … find sort xargs … pipeline I/o redirection

UNIX Philosophy Small is beautiful. Make each program do one thing well. Build a prototype as soon as possible. Choose portability over efficiency. Store data in flat text files. Use software leverage to your advantage. Use shell scripts to increase leverage and portability. Avoid captive user interfaces. Make every program a filter.

Linus Torvalds Really, I’m not out to destroy Microsoft. That will just be a completely unintentional side effect. Software is like sex; it’s better when it’s free. Talk is cheap. Show me the code. Those that can, do. Those that can’t, complain.