@bun-win32/wlanapi

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

Overview

@bun-win32/wlanapi exposes the wlanapi.dll exports using Bun's FFI. It provides a single class, Wlanapi, 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 wlanapi.dll (Native Wifi, hosted network, and Wi-Fi Direct APIs).
• In-source docs in structs/Wlanapi.ts with links to Microsoft Learn.
• Lazy binding on first call; optional eager preload (Wlanapi.Preload()).
• No wrapper overhead; calls map 1:1 to native APIs.
• Strongly-typed Win32 aliases, enums, and constants (see types/Wlanapi.ts).

Requirements

• Bun runtime
• Windows 10 or later

Installation

bun add @bun-win32/wlanapi

Quick Start

import { type Pointer, read, toArrayBuffer } from 'bun:ffi';

import Wlanapi, { WLAN_API_VERSION_2_0 } from '@bun-win32/wlanapi';

const negotiatedVersion = Buffer.alloc(4);
const clientHandle = Buffer.alloc(8);

const openStatus = Wlanapi.WlanOpenHandle(WLAN_API_VERSION_2_0, null, negotiatedVersion.ptr, clientHandle.ptr);

if (openStatus !== 0) {
  throw new Error(`WlanOpenHandle failed with status ${openStatus}`);
}

const handle = clientHandle.readBigUInt64LE(0);
const interfaceList = Buffer.alloc(8);

try {
  const enumStatus = Wlanapi.WlanEnumInterfaces(handle, null, interfaceList.ptr);

  if (enumStatus !== 0) {
    throw new Error(`WlanEnumInterfaces failed with status ${enumStatus}`);
  }

  const listPointer = read.ptr(interfaceList.ptr) as Pointer;

  if (listPointer) {
    const listHeader = new DataView(toArrayBuffer(listPointer, 0, 8));
    const interfaceCount = listHeader.getUint32(0, true);

    console.log(`Wireless interfaces: ${interfaceCount}`);

    Wlanapi.WlanFreeMemory(listPointer);
  }
} finally {
  Wlanapi.WlanCloseHandle(handle, null);
}

[!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 example:

bun run example

Notes

• Either rely on lazy binding or call Wlanapi.Preload().
• Windows only. Bun runtime required.
• 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.