libusb/libusb
Libusb
libusb is a cross-platform user-space library that provides a consistent C API for discovering, configuring, and communicating with USB devices from applications. It abstracts operating-system-specific USB driver details behind a single interface that works on Linux, macOS, Windows, and other platforms, enabling developers to write portable USB code without platform-specific knowledge.
The library supports both synchronous and asynchronous I/O models for USB transfers. Synchronous operations block the calling thread until a transfer completes, offering a straightforward sequential programming model, while asynchronous operations start non-blocking transfers and invoke a user-supplied callback upon completion, enabling concurrent data flows. All functions return negative integer error codes that map to documented constants, allowing callers to diagnose failures without exceptions. The library also provides structured diagnostic output to standard error, activated through an API call or environment variable, to aid troubleshooting.
For device management, libusb includes a hotplug event polling mechanism that monitors system device notifications on supported platforms and fires a registered callback when a USB device is attached or removed during runtime. The library handles control, bulk, interrupt, and isochronous transfer types, routing each through separate code paths that match the USB protocol’s timing and data rules.
Features
- USB Device Communication - Provides a cross-platform C API for control, bulk, interrupt, and isochronous USB data transfers.
- USB Endpoint Transfers - Sends control, bulk, interrupt, and isochronous data between a host and USB device via endpoint transfers.
- Asynchronous USB Transfer Engines - Starts non-blocking USB I/O operations that notify completion via callbacks for greater concurrency.
- Cross-Platform USB Access - Provides a consistent C API for discovering and communicating with USB devices across Linux, macOS, and Windows.
- USB - Enables non-blocking USB data transfers with completion notification for concurrent application designs.
- USB Asynchronous Transfers - Provides non-blocking USB transfers with callback-based completion notification for concurrent application designs.
- Synchronous Blocking I/O - Provides synchronous blocking USB transfers for a straightforward sequential programming interface.
- USB Synchronous Transfers - Runs USB I/O operations that block until completion, providing a simple sequential programming model.
- Platform Abstraction Layers - Hides OS-specific USB driver details behind a single C API that works across Linux, macOS, and Windows.
- Cross-Platform USB Libraries - Provides a consistent user-space API to discover, configure, and communicate with USB devices across operating systems.
- Transfer Type Routing - Routes control, bulk, interrupt, and isochronous requests through separate code paths matching USB protocol rules.
- USB Error Diagnosis - Interprets negative error codes from USB operations to identify and troubleshoot device communication failures.
- USB Error Code Mappings - Maps negative error codes from USB function calls to documented constants for diagnosing device communication failures.
- Hotplug Callback Registration - Triggers registered callbacks when USB devices are attached or removed on supported platforms during runtime.
- Runtime Hotplug Detection - Receives notifications when USB devices are attached or removed from the system during runtime via polling.
- USB Hotplug Event Handlers - Implements a hotplug polling mechanism that fires callbacks when USB devices are attached or removed during runtime.
- USB Hotplug Polling - Monitors system device notifications and fires callbacks when USB devices are attached or removed during runtime.
- Negative Error Code Returns - Returns negative integer error codes from all functions, enabling callers to diagnose failures without exceptions.
- USB Error Code Interpreters - Ships a convention of returning negative error codes that map to documented constants for diagnosing USB communication failures.
- Systèmes embarqués - User-space USB communication library.
- General Libraries - Generic access library for USB devices.
