@bun-win32/xinput9_1_0

Zero-dependency, zero-overhead Win32 XInput 9.1.0 bindings for Bun on Windows.

Overview

@bun-win32/xinput9_1_0 exposes the xinput9_1_0.dll exports using Bun's FFI. It provides a single class, Xinput9_1_0, which lazily binds native symbols on first use. You can optionally preload a subset or all symbols up-front via Preload().

The bindings are strongly typed for a smooth DX in TypeScript.

Features

• Bun-first ergonomics on Windows 10/11.
• Direct FFI to xinput9_1_0.dll (legacy Xbox controller input and vibration).
• In-source docs in structs/Xinput9_1_0.ts with links to Microsoft Docs.
• Lazy binding on first call; optional eager preload (Xinput9_1_0.Preload()).
• No wrapper overhead; calls map 1:1 to native APIs.
• Strongly-typed Win32 aliases (see types/Xinput9_1_0.ts).

Requirements

• Bun runtime
• Windows 10 or later

Installation

bun add @bun-win32/xinput9_1_0

Quick Start

import Xinput9_1_0 from '@bun-win32/xinput9_1_0';

const ERROR_SUCCESS = 0;
const state = Buffer.alloc(16); // XINPUT_STATE

const result = Xinput9_1_0.XInputGetState(0, state.ptr);

if (result === ERROR_SUCCESS) {
  const buttons = state.readUInt16LE(4);
  const lx = state.readInt16LE(8);
  const ly = state.readInt16LE(10);
  console.log(`Buttons: 0x${buttons.toString(16)}, Left stick: (${lx}, ${ly})`);
} else {
  console.log('No controller on slot 0');
}

[!NOTE] AI agents: see AI.md for the package binding contract and source-navigation guidance. It explains how to use the package without scanning the entire implementation.

Examples

Run the included examples:

bun run example:gamepad-monitor
bun run example:controller-report

Notes

• Either rely on lazy binding or call Xinput9_1_0.Preload().
• Windows only. Bun runtime required.
• For new projects, prefer @bun-win32/xinput1_4 which provides additional APIs (battery, keystroke, audio device IDs).
• SAL types & naming: nullability is in the type — Optional<T> (formally optional, SAL _*opt_) and Nullable<T> (plain [in]/[out] the docs say can be NULL), the null sentinel derived from T (null for pointers LP*/P*, 0n for handles/by-value addresses); direction is in the parameter name — _out (_Out_), _in_out (_Inout_), _In_ bare. See AI.md and the repo AGENTS.md.