aandom / pipex

Pipex

Description

Pipex is a project designed to replicate the functionality of the shell command pipeline in Unix-like operating systems. The project requires the creation of a program that mimics the behavior of the shell command "< file1 cmd1 | cmd2 > file2". This involves taking four parameters: two input file names (file1 and file2) and two commands (cmd1 and cmd2). The program then executes the two commands in parallel, with the output of cmd1 serving as the input to cmd2, and writes the result to file2.

Pipex serves as a practical exercise helpful on understanding of process management, file descriptors, and inter-process communication in Unix systems.

Description

this project employs various system calls and techniques to achieve its functionality:

• Forking: The program creates child processes using the fork system call to execute the specified commands concurrently.
• Piping: It establishes communication channels between the child processes using the pipe system call to create a pipeline for data transfer.
• Command Execution: The execve system call is used to replace the child process image with the specified commands, allowing them to be executed.
• File Redirection: The program redirects the standard input and output of the child processes to the appropriate files using file descriptors.

Installation

1. Clone the repository:

   git clone https://github.com/aandom/pipex.git

2. Navigate to the project directory:

   cd pipex

3. Compile the program:

   make

Usage

To use pipex, follow the following steps:

1. Provide the input and output file names, as well as the two commands as arguments:

   ./pipex file1 cmd1 cmd2 file2

2. The program will execute the two commands in parallel, with the output of cmd1 serving as the input to cmd2. The result will be written to file2.

Example:

./pipex infile "ls -l" "grep pipex" outfile

Bonus Features

1. Compile the program:

   make bonus

• Support Heredoc File (<<) and Append (>>)

  • The program supports appending output to a file using the >> operator.
  • The program supports the use of heredoc files as input. Heredoc files allow for inline input.

  Example:

  ./pipex here_doc LIMITER "cmd1" "cmd2" "cmd3 file2

• Handle Multiple pipes

  • Pipex 42 can handle more than two commands in the pipeline. Simply provide additional commands as arguments.

  Example:

  ./pipex file1 cmd1 cmd2 cmd3 file2