SMALLSH

Introduction

My own shell written in C which implements a command line interface similar to well-known shells, such as bash.

The program:

Prints an interactive input prompt
Parses command line input into semantic tokens
Implements parameter expansion
- Shell special parameters $$, $?, and $!
- Tilde (~) expansion
Implements two shell built-in commands: exit and cd
Executes non-built-in commands using the the appropriate EXEC(3) function.
Implements redirection operators ‘<’ and ‘>’
Implements the ‘&’ operator to run commands in the background
Implements custom behavior for SIGINT and SIGTSTP signals

Program Functionality

Input
Word splitting
Expansion
Parsing
Execution
Waiting