@bun-win32/shlwapi

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

Overview

@bun-win32/shlwapi exposes the shlwapi.dll exports using Bun's FFI. It provides a single class, Shlwapi, 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 shlwapi.dll (paths, strings, URLs, registry, streams, and more).
• In-source docs in structs/Shlwapi.ts with links to Microsoft Docs.
• Lazy binding on first call; optional eager preload (Shlwapi.Preload()).
• No wrapper overhead; calls map 1:1 to native APIs.
• Strongly-typed Win32 aliases (see types/Shlwapi.ts).

Requirements

• Bun runtime
• Windows 10 or later

Installation

bun add @bun-win32/shlwapi

Quick Start

import Shlwapi from '@bun-win32/shlwapi';

const encode = (str: string) => Buffer.from(`${str}\0`, 'utf16le');

// Optionally bind a subset up-front
Shlwapi.Preload(['PathFileExistsW', 'StrCmpLogicalW']);

const exists = Shlwapi.PathFileExistsW(encode('C:\\Windows').ptr);
console.log('C:\\Windows exists: %s', exists === 1);

const cmp = Shlwapi.StrCmpLogicalW(encode('file2.txt').ptr, encode('file10.txt').ptr);
console.log('file2.txt < file10.txt: %s', cmp < 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              # Path and string utility demos

Notes

• Either rely on lazy binding or call Shlwapi.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.