Windows USER

Last updated

Windows USER is a component of the Microsoft Windows operating system that provides core functionality for building simple user interfaces. The component has existed in all versions of Windows, and includes functionality for window management, message passing, input processing and standard controls.

Contents

Functionality and role

Windows USER provides a large part of the core user experience for Microsoft Windows. Historically, it was responsible for: [1] [2]

Gradually, as Windows has become larger and better factored, Windows USER has cooperated with other components to provide this functionality:

Developer experience

Windows USER implements abstractions that are used to build Windows applications. These include

The HWND is the basic unit of visual display and input in the Windows developer platform. All visual elements either have their own HWNDs or live as part of a larger HWND. Many functions in Windows USER manipulate properties on HWNDs such as size, position and title. Each HWND also has a communication channel (WNDPROC - Window Procedure) for delivery of messages.

Windows are managed as a tree, with the desktop window at the root of the hierarchy. Child windows are usually (but not always) visually contained within their parents.

Applications and the operating system communicate with HWNDs using messages. A window message is the combination of a target HWND, a message code, and other details such as mouse position.

By combining calls to Windows USER in the right way, a Windows application processes messages. The core Windows message loop (including calls to GetMessage, TranslateMessage and DispatchMessage) is at the core of any Windows application.

Developer functionality related to Windows USER is provided in the C header file winuser.h.

Implementation

In 16-bit versions of Windows, Windows USER was implemented as a file called user.exe. The file extension here was a misnomer, as Windows USER was in fact always a dynamic link library.

In 32-bit versions of Windows, the 32-bit version of Windows USER is called user32.dll and is located in the System32 directory, while compatibility with 16-bit applications is provided by having a modified version of user.exe also present.

In 64-bit versions of Windows, the 64-bit implementation of Windows USER is called user32.dll and is located in the System32 directory, while a modified 32-bit version (also called user32.dll) is present in the SysWOW64 directory.

See also

Related Research Articles

VBScript is an Active Scripting language developed by Microsoft that is modeled on Visual Basic. It allows Microsoft Windows system administrators to generate powerful tools for managing computers without error handling and with subroutines and other advanced programming constructs. It can give the user complete control over many aspects of their computing environment.

Visual Basic for Applications (VBA) is an implementation of Microsoft's event-driven programming language Visual Basic 6.0 built into most desktop Microsoft Office applications. Although based on pre-.NET Visual Basic, which is no longer supported or updated by Microsoft, the VBA implementation in Office continues to be updated to support new Office features. VBA is used for professional and end-user development due to its perceived ease-of-use, Office's vast installed userbase, and extensive legacy in business.

<span class="mw-page-title-main">Windows 95</span> Microsoft computer operating system released in 1995

Windows 95 is a consumer-oriented operating system developed by Microsoft as part of its Windows 9x family of operating systems. The first operating system in the 9x family, it is the successor to Windows 3.1x, and was released to manufacturing on July 14, 1995, and generally to retail on August 24, 1995, almost three months after the release of Windows NT 3.51. Windows 95 merged Microsoft's formerly separate MS-DOS and Microsoft Windows products, and featured significant improvements over its predecessor, most notably in the graphical user interface (GUI) and in its simplified "plug-and-play" features. There were also major changes made to the core components of the operating system, such as moving from a mainly cooperatively multitasked 16-bit architecture to a 32-bit preemptive multitasking architecture, at least when running only 32-bit protected mode applications.

<span class="mw-page-title-main">Wine (software)</span> Windows compatibility software

Wine is a free and open-source compatibility layer that aims to allow application software and computer games developed for Microsoft Windows to run on Unix-like operating systems. Wine also provides a software library, named Winelib, against which developers can compile Windows applications to help port them to Unix-like systems.

<span class="mw-page-title-main">Windows API</span> Microsofts core set of application programming interfaces on Windows

The Windows API, informally WinAPI, is Microsoft's core set of application programming interfaces (APIs) available in the Microsoft Windows operating systems. The name Windows API collectively refers to several different platform implementations that are often referred to by their own names. Almost all Windows programs interact with the Windows API. On the Windows NT line of operating systems, a small number use the Native API.

Object Linking & Embedding (OLE) is a proprietary technology developed by Microsoft that allows embedding and linking to documents and other objects. For developers, it brought OLE Control Extension (OCX), a way to develop and use custom user interface elements. On a technical level, an OLE object is any object that implements the IOleObject interface, possibly along with a wide range of other interfaces, depending on the object's needs.

<span class="mw-page-title-main">Text-based user interface</span> Type of interface based on outputting to or controlling a text display

In computing, text-based user interfaces (TUI), is a retronym describing a type of user interface (UI) common as an early form of human–computer interaction, before the advent of modern conventional graphical user interfaces (GUIs). Like GUIs, they may use the entire screen area and accept mouse and other inputs. They may also use color and often structure the display using special graphical characters such as ┌ and ╣, referred to in Unicode as the "box drawing" set. The modern context of use is usually a terminal emulator.

<span class="mw-page-title-main">Windows Forms</span> Graphical user interface software library is Windows Explorer.

Windows Forms (WinForms) is a free and open-source graphical (GUI) class library included as a part of Microsoft .NET, .NET Framework or Mono, providing a platform to write client applications for desktop, laptop, and tablet PCs. While it is seen as a replacement for the earlier and more complex C++ based Microsoft Foundation Class Library, it does not offer a comparable paradigm and only acts as a platform for the user interface tier in a multi-tier solution.

Windows Presentation Foundation (WPF) is a free and open-source graphical subsystem originally developed by Microsoft for rendering user interfaces in Windows-based applications. WPF, previously known as "Avalon", was initially released as part of .NET Framework 3.0 in 2006. WPF uses DirectX and attempts to provide a consistent programming model for building applications. It separates the user interface from business logic, and resembles similar XML-oriented object models, such as those implemented in XUL and SVG.

<span class="mw-page-title-main">Architecture of Windows NT</span> Overview of the architecture of the Microsoft Windows NT line of operating systems

The architecture of Windows NT, a line of operating systems produced and sold by Microsoft, is a layered design that consists of two main components, user mode and kernel mode. It is a preemptive, reentrant multitasking operating system, which has been designed to work with uniprocessor and symmetrical multiprocessor (SMP)-based computers. To process input/output (I/O) requests, they use packet-driven I/O, which utilizes I/O request packets (IRPs) and asynchronous I/O. Starting with Windows XP, Microsoft began making 64-bit versions of Windows available; before this, there were only 32-bit versions of these operating systems.

The graphical identification and authentication (GINA) is a component of Windows NT 3.51, Windows NT 4.0, Windows 2000, Windows XP and Windows Server 2003 that provides secure authentication and interactive logon services. GINA is a replaceable dynamically linked library that is loaded early in the boot process in the context of Winlogon when the machine is started. It is responsible for handling the secure attention sequence, typically Control-Alt-Delete, and interacting with the user when this sequence is received. GINA is also responsible for starting initial processes for a user (such as the Windows Shell) when they first log on. GINA is discontinued in Windows Vista.

Dynamic-link library (DLL) is Microsoft's implementation of the shared library concept in the Microsoft Windows and OS/2 operating systems. These libraries usually have the file extension DLL, OCX, or DRV . The file formats for DLLs are the same as for Windows EXE files – that is, Portable Executable (PE) for 32-bit and 64-bit Windows, and New Executable (NE) for 16-bit Windows. As with EXEs, DLLs can contain code, data, and resources, in any combination.

As the next version of Windows NT after Windows 2000, as well as the successor to Windows Me, Windows XP introduced many new features but it also removed some others.

The Microsoft Windows operating system supports a form of shared libraries known as "dynamic-link libraries", which are code libraries that can be used by multiple processes while only one copy is loaded into memory. This article provides an overview of the core libraries that are included with every modern Windows installation, on top of which most Windows applications are built.

<span class="mw-page-title-main">Visual Basic (classic)</span> Event-driven programming language

The original Visual Basic is a third-generation event-driven programming language from Microsoft known for its Component Object Model (COM) programming model first released in 1991 and declared legacy during 2008. Microsoft intended Visual Basic to be relatively easy to learn and use. Visual Basic was derived from BASIC and enables the rapid application development (RAD) of graphical user interface (GUI) applications, access to databases using Data Access Objects, Remote Data Objects, or ActiveX Data Objects, and creation of ActiveX controls and objects.

Microsoft UI Automation (UIA) is an application programming interface (API) that allows one to access, identify, and manipulate the user interface (UI) elements of another application.

Component Object Model (COM) is a binary-interface standard for software components introduced by Microsoft in 1993. It is used to enable inter-process communication object creation in a large range of programming languages. COM is the basis for several other Microsoft technologies and frameworks, including OLE, OLE Automation, Browser Helper Object, ActiveX, COM+, DCOM, the Windows shell, DirectX, UMDF and Windows Runtime. The essence of COM is a language-neutral way of implementing objects that can be used in environments different from the one in which they were created, even across machine boundaries. For well-authored components, COM allows reuse of objects with no knowledge of their internal implementation, as it forces component implementers to provide well-defined interfaces that are separated from the implementation. The different allocation semantics of languages are accommodated by making objects responsible for their own creation and destruction through reference-counting. Type conversion casting between different interfaces of an object is achieved through the QueryInterface method. The preferred method of "inheritance" within COM is the creation of sub-objects to which method "calls" are delegated.

In computing, Nano-X is a windowing system which is full featured enough to be used on a PC, an embedded system or a PDA. It is an Open Source project aimed at bringing the features of modern graphical windowing environments to smaller devices and platforms. The project was renamed from Microwindows due to legal threats from Microsoft regarding the Windows trademark.

XBLite is a free Open Source BASIC programming language compiler and development system. It was started in 2001 by David Szafranski in order to provide a Windows exclusive version of the XBasic dialect. XBLite is released under the GNU GPL licensing scheme, Standard libraries are released under the GNU LGPL licensing scheme.

<span class="mw-page-title-main">Architecture of Windows 9x</span>

The Windows 9x series of operating systems refers to the kernel which lies at the heart of Windows 9x. Its architecture is monolithic.

References

  1. Petzold, Charles (1998). Programming Windows Fifth Edition, Microsoft Press, ISBN   978-1-57231-995-0 .
  2. Chen, Raymond (2007). The Old New Thing, Addison-Wesley Professional, ISBN   978-0-321-44030-3
  3. Windows Ribbon Framework