Terminal

Question 1

output text in red using CONSOLE_CODES

Answer 1

printf '\x1b[31hello!\x1b[0m\n'
- switch to red
- hello!
- switch back
- line feed 
\x

Question 2

Influence of teletype machine input

Answer 2

• Compact and concise input syntax, making full use of ASCII repertoire to minimise keystrokes
• Output format should be simple and easily usable as input for other programs to parse e.g. one record per line – then we can combine many tools

Question 3

Composition of tools

Answer 3

• Programs can be joined together in “pipes” and

- “scripts” to solve more complex problems: call unix tools as subroutines

Question 4

Evolution of many parameters

Answer 4

• Each tool originally performed a simple single function
• Prefer reusing existing tools with minor extension to rewriting a new
  tool from scratch

Question 5

Shell

Answer 5

The main user-interface software (“shell”) is a normal replaceable program without special privileges

• Not part of the kernel … many competing shells developed
• Turned into a full featured programming language to implement scripts that automate routine tasks