MyShell

The goal of this project is to build a shell interpreter which combines behavior from common shells including bash and csh.

What I implemented

Part 1: Parsing and Executing Commands

• Part 1A: Lex and Yacc - Accepting more complex commands
• Part 1B: Executing commands
  1B.1: Simple command process creation and execution
  1B.2: File redirection
  1B.3: Pipes
  1B.4: isatty()
  

Part 2: Signal Handling, More Parsing, and Subshells

• 2.1: Ctrl-C
• 2.2: Zombie Elimination
• 2.3: Exit
• 2.4: Quotes
• 2.5: Escaping
• 2.6: Builtin Functions (printenv, setenv A B, unsetenv A, source A, cd A)
• 2.7: Creating a Default Source File: “.shellrc”
• 2.8: Subshells

Part 3: Expansions, Wildcards, and Line Editing

• 3.1: Environment variable expansion "$, ?, !, _, SHELL"
• 3.2: Tilde expansion
• 3.3: Wildcarding
• 3.4: Edit mode
• 3.5: History
• 3.6: Path completion
• 3.7: Variable prompt