42sh — POSIX Shell

A fully functional POSIX-compliant shell interpreter written in C, capable of executing real shell commands with advanced features.

Supports pipelines (cmd1 | cmd2), logical operators (&& and ||), command lists (semicolons), and multiple types of I/O redirections — covering a significant subset of the POSIX shell specification.

Built using the autoconf/automake toolchain for portable compilation across Unix systems. The build process follows the standard configure/make pattern.

The shell can be invoked interactively or via the -c flag for one-shot command execution, making it usable both as a user shell and a scripting tool.

This project demonstrates deep understanding of systems programming: process management with fork/exec, file descriptor manipulation, signal handling, and tokenization/parsing of shell grammar.