@bun-win32/mpr

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

Overview

@bun-win32/mpr exposes the mpr.dll exports using Bun's FFI. It provides a single class, Mpr, 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 mpr.dll (network drive mapping, UNC connections, resource enumeration).
• In-source docs in structs/Mpr.ts with links to Microsoft Docs.
• Lazy binding on first call; optional eager preload (Mpr.Preload()).
• No wrapper overhead; calls map 1:1 to native APIs.
• Strongly-typed Win32 aliases (see types/Mpr.ts).

Requirements

• Bun runtime
• Windows 10 or later

Installation

bun add @bun-win32/mpr

Quick Start

import Mpr, { WN_NO_ERROR } from '@bun-win32/mpr';

// Get the current network user
const userBuf = Buffer.alloc(512);
const sizeBuf = Buffer.alloc(4);
sizeBuf.writeUInt32LE(256, 0);

const result = Mpr.WNetGetUserW(null, userBuf.ptr, sizeBuf.ptr);

if (result === WN_NO_ERROR) {
  const user = userBuf.toString('utf16le').replace(/\0.*$/, '');
  console.log(`Network user: ${user}`);
}

[!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:net-explorer
bun run example:drive-audit

Notes

• Either rely on lazy binding or call Mpr.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.