Unix philosophy and principles

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Transcript of Unix philosophy and principles

Linux Philosophy and principles

Unix philosophy The Unix philosophy, originated by Ken Thompson, is a set of cultural norms and philosophical approaches to developing small software's.

Linux philosophy 1) Everything is a file. 2) Small, single-purpose programs.3) Ability to chain programs together to perform complex tasks.

4) Avoid captive user interfaces.5) Configuration data stored in text.

Everything is a file: UNIX systems have many powerful utilities designed to create and manipulate files.

Small, single purpose programs UNIX provides many small utilities that perform one task very well.

Chaining programs together

A core design feature of UNIX is that the output of one program can be the input for another.

Avoid captive users interfaces:

Interactive commands are rare in UNIX. Most commands expect their options and arguments to be typed on the command line.

Configuration data stored in text.Text is a universal interface, and many UNIX utilities exist to manipulate text.

Origin

Doug McIlroy attributes the philosophy of combining "small, sharp tools "to accomplish larger tasks to Ken Thompson, one of the creators of Unix.

Unix programing environment

Even though the UNIX system introduces a number of innovative programs and techniques, no single program or idea makes it work well.

Program design

Much of the power of the UNIX operating system comes from a style of program design that makes programs easy to use and easy to combine with other programs.

Eric Raymond’s 17 Unix Rules

Rule of Modularity

Rule of Clarity

Rule of Composition

Rule of Separation

Rule of Simplicity Rule of Parsimony Rule of Transparency And more….

Rule of Modularity This rule aims to

save time on debugging code that is complex, long, and unreadable.

Rule of ClarityThis rule aims to make code readable and comprehensible for whoever works on the code in future.

Rule of Composition This rule aims to allow developers to break

down projects into small, simple programs rather than overly complex monolithic programs.

Rule of SeparationThis rule aims to let policies be changed without destabilizing mechanisms and consequently reducing the number of bugs.

This rule aims to discourage developers’ affection for writing “intricate and beautiful complexities” that are in reality bug prone programs.

Rule of ParsimonyThis rule aims to prevent overinvestment

of development time in failed or suboptimal approaches caused by the owners of the program’s reluctance to

throw away visibly large pieces of work.

Rule of Transparency

This rule aims to reduce debugging time and extend the lifespan of programs.

https://linuxtutorials4u.wordpress.com/2011/09/03/linux-principles/

https://en.wikipedia.org/wiki/Unix_philosophy