shellB

A basic command-line tool (REPL) that supports executing commands, handling executable paths, and redirecting output to files. It demonstrates various functionalities such as interpreting commands, executing system commands, and handling input/output redirection.

Features

• Command Execution: Allows you to execute commands from your system's PATH.
• Echo Command: Outputs input to the console or redirects it to a file.
• Custom Command Handling: Users can define custom commands to be executed.
• File Output Handling: Supports redirection of output (standard output and error output) to files.

Prerequisites

• C++17 or higher
• A C++ compiler (e.g., g++ or clang++)
• Cmake
• vcpkg

Installation

1. Clone the repository:

   git clone https://github.com/Rachit2912/shellB.git

2. Navigate to the project directory:

   cd shellB

3. Compile the program: open wsl (windows subsustem for linux) in the shellB folder and run this command :

   vim shellB.sh

   press 'i' and now edit the vcpkg directory where vcpkg is installed and save by pressing 'esc' => ':wq'
4. Run the program:

   ./shellB.sh

Usage

Once the program starts, you will be prompted with a basic REPL interface. You can input commands, such as:

• *** echo ***: Output text to the console.
• *** pwd *** : Prints the current working directory
• *** cd *** : Changing the directory (supports absolute,relative paths, ./ , ../ , ~ & many more linux file standards)
• *** > / 1> *** : Output redirection to a file
• *** 2> *** : Error redirection to a file
• *** >> / 1>> *** : Output addition to a file
• *** 2>> *** : Error addition to a file
• *** exit 0 ***: Exit the program
• *** RJ *** : About section of the shell

How It Works

1. Command Parsing: The program reads user input, parses the command, and executes the corresponding action.
2. Command Mapping: Commands like exit, echo, pwd, cd & RJ are mapped to functions using std::map.
3. Path Lookup: The program can search for executables within directories specified in the system's PATH environment variable.
4. Output Redirection: Supports >, 1>, 2>, >>, 1>>, and 2>> for redirecting output to files.