https://blog.fulgen.dev/tags/win32/ Recent content in Win32 on Fulgen's Blog Hugo en Sat, 10 May 2025 14:45:15 +0200 https://blog.fulgen.dev/posts/await-getmessage/ Sat, 10 May 2025 14:45:15 +0200 https://blog.fulgen.dev/posts/await-getmessage/ <p>Windows has quite decent support for asynchronous operations in its APIs. And while, as is typical for, sadly, any OS, it comes in multiple forms and fashions like <code>ReadFile</code>&rsquo;s &ldquo;signal an event when done&rdquo; and APCs, the ruler of them all are I/O Completion Ports, introduced in NT 3.5, 31 years ago. Unsurprisingly, it is completion based - instead of polling for when an operation has finished like the eponymous <code>poll</code>, operations post a completion when they&rsquo;re done, and the caller just has to wait for and handle completions. IOCPs are also the core of the Windows Threadpool API, where you don&rsquo;t even have to deal with a port directly - you register a callback, and the system calls it for you when it dequeues the completion.</p>