Pipex

The Pipex project is a challenge within the 42 School curriculum aimed at deepening students' understanding of process management, inter-process communication (IPC), and the use of Unix system calls in C. The goal is to replicate the behavior of the shell pipe (|) by chaining multiple commands together, passing the output of one command as the input to the next.

Task

The task was to implement a program that replicates the functionality of the Unix pipe (|) for two commands. The program needs to handle various tasks such as:

• Executing two commands with the first command's output being piped to the second command's input.
• Managing file descriptors, duplicating them as necessary to redirect input and output.
• Handling errors gracefully, including command execution failures, invalid arguments, and file access issues.

Key objectives included:

• Implementing a program that mimics the following shell command: < file1 cmd1 | cmd2 > file2, where the output of cmd1 reading from file1 is piped to cmd2, which writes to file2.
• Ensuring the program correctly handles edge cases, such as missing files, invalid commands, and permission errors.
• Demonstrating a deep understanding of Unix system calls, particularly pipe(), dup2(), fork(), and execve().

Key Achievements

• Successful Process Management: Implemented a robust solution that handles the creation and management of child processes, ensuring proper execution and termination of piped commands.
• Efficient Inter-Process Communication: Developed a reliable pipeline mechanism using Unix pipes, enabling seamless data transfer between commands.
• Comprehensive Error Handling: Integrated extensive error checking and handling to manage edge cases and unexpected scenarios, ensuring the program operates reliably in various conditions.

Installation

To install the Project, follow these steps:

1. Clone the repository: git clone git@github.com:jakobsitory/02_pipex_42CC.git
2. Navigate to the project directory: cd 02_pipex_42CC
3. Build the project: make

Usage

The pipex program should be executed as follows:

./pipex file1 cmd1 cmd2 file2