Shell Project

Overview

This project is a simple shell implementation in C++ that supports executing commands, handling input/output redirection, and piping multiple commands. It demonstrates process management using fork, execvp, and waitpid system calls.

Features

• Command execution
• Input (<), output (>), and error (2>) redirection
• Pipelining (|) support for chaining commands
• Background process execution using &
• Color-coded output for logs and errors

Requirements

To build and run the shell, ensure you have:

• A Linux-based system
• g++ compiler
• Make

Installation & Compilation

# Clone the repository
git clone https://github.com/Ah-Ibrahim/Shell.git
cd /Shell

# Compile the shell
make   # If a Makefile is available

# Then run the shell
./shell

Usage

./shell

Once inside the shell, you can execute commands like:

ls -l
ls | grep .cpp
cat file.txt > output.txt
./script.sh &

Files

├── .gitignore            # Git ignore file
├── command.cc            # Command class implementation
├── command.h             # Command class header file
├── command.o             # Compiled object file
├── lex.yy.c              # Generated lexical analyzer
├── lex.yy.o              # Lexical analyzer object file
├── Makefile              # Compilation instructions
├── process_log.txt       # Log file for processes
├── README.md             # Documentation
├── shell                 # Shell executable
├── shell.l               # Lex file for lexical analysis
├── shell.y               # Yacc/Bison grammar file
├── y.tab.c               # Generated parser code
├── y.tab.h               # Generated parser header
├── y.tab.o               # Parser object file

Issues & Debugging

If you encounter issues:

• Ensure the compiled binary has execution permissions: chmod +x myshell
• Use strace ./myshell to debug system calls
• Add debug prints in execute() to track fork and execvp behavior

Author

Developed by Ahmed Ibrahim. Contributions and feedback are welcome!