Windows API Reference - Documentation

API Reference - Windows Documentation

Welcome to the comprehensive API Reference for the Windows Operating System. This section details the various functions, structures, and constants that form the backbone of Windows application development.

Introduction to Windows APIs

The Windows API (Application Programming Interface) provides a set of functions and interfaces that allow applications to interact with the Windows operating system. These APIs cover a vast range of functionalities, from basic input/output operations and memory management to advanced graphics rendering, networking, and user interface creation.

Key Components:

Win32 API: The primary API for Windows applications, offering access to system services and features.
Core Libraries: Essential DLLs like Kernel32.dll (process management, memory, I/O), User32.dll (window management, input), and Gdi32.dll (graphics).
COM (Component Object Model): A system for creating and interacting with reusable software components.
.NET Framework/Core: A managed execution environment and class library providing a higher-level abstraction over native APIs.

Note: This documentation focuses primarily on the native Win32 API. For .NET specific information, please refer to the official .NET documentation.

Navigating the API Reference

Use the navigation pane on the left to explore different categories of APIs. You can find detailed information on specific functions, their parameters, return values, and usage examples.

Common Sections for each API Entry:

Syntax: The function signature and declaration.
Parameters: Detailed description of each input parameter.
Return Value: What the function returns upon successful or failed execution.
Remarks: Important notes, usage guidelines, and potential caveats.
Requirements: Minimum operating system versions and related libraries.
See Also: Links to related functions or concepts.

Example: Getting System Information

Let's look at a common task: retrieving the operating system version. The GetVersionEx function (though now largely superseded by GetVersion or the more robust methods) was a classic example:

`GetVersionEx` Function

Retrieves version information about the currently running Windows operating system.

Syntax

BOOL GetVersionEx(
  LPOSVERSIONINFO lpVersionInformation
);

Parameters

Parameter	Description
`lpVersionInformation`	A pointer to an `OSVERSIONINFO` structure that receives the operating system version information. You must initialize the `dwOSVersionInfoSize` member of this structure.

Return Value

If the function succeeds, the return value is non-zero. If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

Modern applications should generally use VerifyVersionInfo or GetVersion. GetVersionEx is provided for backward compatibility. It's crucial to set the dwOSVersionInfoSize member correctly before calling this function.

Important: For new development, consider using the RtlGetVersion function which provides more detailed and accurate version information, especially on newer Windows versions.

Common API Categories to Explore:

This reference aims to be a definitive guide for developers working with the Windows platform. Happy coding!