A terminal session recorder and replayer written in C that allows you to capture and replay terminal sessions with precise timing. ⚠️ Disclaimer This is a hobby project created for fun and learning purposes. It's still in active development and may contain bugs or incomplete features. If you encounter any issues, please report them in the Issues section. Contributions are welcome and encouraged! Features Record terminal sessions : Capture all terminal input/output with accurate timing information : Capture all terminal input/output with accurate timing information Replay sessions : Play back recorded sessions with original timing : Play back recorded sessions with original timing Session analysis : Analyze recorded sessions with detailed statistics and insights : Analyze recorded sessions with detailed statistics and insights JSON format : Sessions are stored in a structured JSON format for easy parsing : Sessions are stored in a structured JSON format for easy parsing Signal handling : Graceful shutdown and file closure on interruption : Graceful shutdown and file closure on interruption Lightweight : Minimal dependencies, written in pure C : Minimal dependencies, written in pure C Web browser player: Advanced browser-based player with interactive timeline and controls Building Prerequisites GCC compiler GNU Make Standard C library with GNU extensions Git (for cloning project and submodules) Cloning the repository This project uses cJSON as a Git submodule. Make sure to clone with submodules: git clone --recurse-submodules https://github.com/debba/rewindtty.git If you already cloned the repository without submodules, run: git submodule update --init --recursive Compilation make This will create the executable at build/rewindtty . To clean build artifacts: make clean Usage Recording a Session To start recording a terminal session: ./build/rewindtty record [file] This will create a new session file (defaults to data/session.json if no file is specified) and begin capturing all terminal activity. Replaying a Session To replay a previously recorded session: ./build/rewindtty replay [file] This will read the session file (defaults to data/session.json if no file is specified) and replay it with the original timing. Analyzing a Session To analyze a recorded session and get detailed statistics: ./build/rewindtty analyze [file] This will generate a comprehensive analysis report including: Total commands executed and session duration Average time per command Most frequently used commands Slowest commands Commands that generated errors or warnings Helpful suggestions for optimization Command Line Options Usage: rewindtty [record|replay|analyze] [file] Commands: record [file] Start recording a new terminal session to specified file (default: data/session.json) replay [file] Replay a recorded session from specified file (default: data/session.json) analyze [file] Analyze a recorded session and generate statistics report (default: data/session.json) Browser Player The browser_player directory contains an advanced web-based player for rewindtty sessions that provides enhanced features and a modern interface. Features Interactive timeline : Visual timeline with scrubbing support for easy navigation : Visual timeline with scrubbing support for easy navigation Command list : Sidebar showing all executed commands with click-to-jump functionality : Sidebar showing all executed commands with click-to-jump functionality Bookmarks : Add and manage bookmarks at specific moments in the session : Add and manage bookmarks at specific moments in the session Playback controls : Play, pause, restart, and speed adjustment (1x, 2x, 4x, 8x) : Play, pause, restart, and speed adjustment (1x, 2x, 4x, 8x) File loading : Drag-and-drop or file picker support for JSON session files : Drag-and-drop or file picker support for JSON session files Real-time status : Display current command and session timing information : Display current command and session timing information Modern UI: Clean, responsive interface built with TypeScript and Vite Usage Navigate to the browser_player directory: cd browser_player Install dependencies: npm install Start the development server: npm run dev Open your browser and load a JSON session file to start playing Building for Production npm run build The browser player uses xterm.js for terminal emulation and provides a significantly enhanced experience compared to the basic command-line replay functionality. File Structure rewindtty/ ├── src/ │ ├── main.c # Main program entry point │ ├── recorder.c # Session recording functionality │ ├── recorder.h # Recording function declarations │ ├── replayer.c # Session replay functionality │ ├── replayer.h # Replay function declarations │ ├── analyzer.c # Session analysis functionality │ ├── analyzer.h # Analysis function declarations │ ├── utils.c # Utility functions │ └── utils.h # Utility function declarations ├── browser_player/ # Web-based advanced player │ ├── src/ │ │ ├── main.ts # Entry point │ │ ├── player.ts # Player implementation │ │ ├── types.ts # TypeScript type definitions │ │ └── style.css # Player styles │ ├── index.html # HTML template │ ├── package.json # Node.js dependencies │ └── tsconfig.json # TypeScript configuration ├── data/ │ └── session.json # Default session storage file ├── build/ # Build output directory ├── assets/ │ └── demo.gif # Demo animation ├── libs/ │ └── cjson/ # JSON parsing library ├── LICENSE # MIT License ├── Makefile # Build configuration └── README.md # This file Session File Format Sessions are stored in JSON format in the data/session.json file. The format captures timing information and terminal data to enable accurate replay. Signal Handling The recorder handles interruption signals (like Ctrl+C) gracefully by: Closing the session file properly Writing the final JSON structure Cleaning up resources before exit Development Compiler Flags The project uses the following GCC flags: -Wall -Wextra : Enable comprehensive warnings : Enable comprehensive warnings -std=gnu99 : Use GNU C99 standard : Use GNU C99 standard -g : Include debugging symbols Contributing Fork the repository Create a feature branch Make your changes Test thoroughly Submit a pull request License This project is licensed under the MIT License - see the LICENSE file for details. Copyright (c) 2025 Andrea Debernardi Technical Notes