DSH Shell

The DSH Shell is a straightforward implementation of a shell in the C programming language. It provides basic functionalities such as executing commands, managing paths, redirecting output, and using pipes.

Overview

This project demonstrates how to implement a basic shell in C. It includes essential features for command execution and process management, making it a useful learning tool for understanding shell internals.

Features

• Command Execution: Execute commands specified within the system path.
• Path Management: Set the command search path using the setpath command.
• Output Redirection: Redirect output using the symbols > and >>.
• Pipes: Support for pipes using the | symbol.

Technical Details

• Code Structure:
  • panic: Prints an error message and terminates execution.
  • prompt: Displays the shell prompt and reads user input.
  • set_path: Sets the search path for commands.
  • path_lookup: Searches for a command within the specified path.
  • rel2abs: Converts a relative path into an absolute path.
  • do_redir: Handles output redirection.
  • do_pipe: Manages the use of pipes.
  • do_exec: Executes a command.
  • main: Governs the shell's lifecycle.

How to Compile and Run

To compile the code, use the following command:

$ gcc -o dsh dsh.c

To execute the shell, use the command:

$ ./dsh

Notes

• This project is intended as an educational example and does not include all the features of a full-fledged shell.
• Due to the use of the sys/wait library, the code must be executed in a Linux environment. It will not function on Windows.

For more details, refer to the GitHub repository.

Credits

This project was developed as part of the "Programming Languages" course. It showcases the implementation of a basic shell in C.

Contributors:

• Stefano Brighenti
• Daniele Buser
• Hicham Benbouzid