Wine (software)

History

Bob Amstadt, the initial project leader, and Eric Youngdale started the Wine project in 1993 as a way to run Windows applications on Linux. It was inspired by two Sun Microsystems' products, the Wabi for the Solaris operating system, and the Public Windows Initiative, which was an attempt to get the Windows API fully reimplemented in the public domain as an ISO standard but rejected due to pressure from Microsoft in 1996. Wine originally targeted 16-bit applications for Windows 3.x, but as of 2010 focuses on 32-bit and 64-bit versions which have become the standard on newer operating systems. The project originated in discussions on Usenet in comp.os.linux in June 1993. Alexandre Julliard has led the project since 1994.

The project has proven time-consuming and difficult for the developers, mostly because of incomplete and incorrect documentation of the Windows API. While Microsoft extensively documents most Win32 functions, some areas such as file formats and protocols have no publicly available specification from Microsoft, it also includes undocumented low-level functions, undocumented behavior and obscure bugs that Wine must duplicate precisely in order to allow some applications to work properly. Consequently, the Wine team has reverse-engineered many function calls and file formats in such areas as thunking.

The Wine project originally released Wine under the same MIT License as the X Window System, but owing to concern about proprietary versions of Wine not contributing their changes back to the core project, work as of March 2002 has used the LGPL for its licensing.

Wine officially entered beta with version 0.9 on 25 October 2005. Version 1.0 was released on 17 June 2008, after 15 years of development. Version 1.2 was released on 16 July 2010, version 1.4 on 7 March 2012, version 1.6 on 18 July 2013. and version 1.8 on 19 December 2015. Development versions are released roughly every two weeks.

Corporate sponsorship

The main corporate sponsor of Wine is CodeWeavers, which employs Julliard and many other Wine developers to work on Wine and on CrossOver, CodeWeavers' supported version of Wine. CrossOver includes some application-specific tweaks not considered suitable for the WineHQ version, as well as some additional proprietary components.

The involvement of Corel for a time assisted the project, chiefly by employing Julliard and others to work on it. Corel had an interest in porting WordPerfect Office, its office suite, to Linux (especially Corel Linux). Corel later cancelled all Linux-related projects after Microsoft made major investments in Corel, stopping their Wine effort.

Other corporate sponsors include Google, which hired CodeWeavers to fix Wine so Picasa ran well enough to be ported directly to Linux using the same binary as on Windows; Google later paid for improvements to Wine's support for Adobe Photoshop CS2. Wine is also a regular beneficiary of Google's Summer of Code program.

Software architecture

As the Template:Microsoft APIs convincingly shows, there are a lot of APIs from Microsoft. The goal of Wine is to implement those APIs fully or partially that are required by programs that the users of Wine wish to run on top of a Unix-like system.

Win32 API

The Win32 function calls (over 10,000 library calls) are collectively called the Win32 API.

DirectX

DirectX is a collection of APIs for rendering, audio and input. While most office software does not make use of these, computer games do. As of 2017, Wine contains a DirectX 9.0c implementation.

Direct3D

Direct3 9

Many games which use a Direct3 9 rendering path can run on top of Wine.

Gallium3D

The Gallium3D driver model creates a module called Gallium3D State Tracker. A free and open-source Gallium3D State Tracker was written for Microsoft Direct3D 9 in C (and another one for Direct3D 10 written in C++ which has not been maintained). After some modification to Wine, it is now possible to use Direct3D 9 games without the requirement to translate Direct3D calls into OpenGL calls, thus gaining a huge performance boost.

Direct3 10

Direct3 11

On December 12, 2016 Phoronix pointed out, that Wine git could run Overwatch (video game).

Microsoft Windows family of operating systems

The concept underlying the Windows API is exactly contrary to the one underlying the concept of the Linux API. The functions comprising the Linux API are simple, with few parameters and few places where there are multiple ways to perform the same operation. Win32 provides very comprehensive interfaces with many parameters, often with three or four ways of doing the same thing, without the programmer actually knowing the costs, as documentation of the involved system calls is not available outside Microsoft. Additionally Win32 mixes low-level and high-level functions together.

The programming interfaces of the Microsoft Windows family of OSes consist largely of dynamic-link libraries (DLLs). These contain a huge number of wrapper sub-routines for the system calls of the kernel, the NTOS kernel-mode program (ntoskrnl.exe). Only programmers at Microsoft write to the system-call layer, as documentation is not publicly available. The published user-mode interfaces all belong to operating system personalities that are implemented using subsystems that run on top of the NTOS layers. As a result, a programmer never knows the cost of sub-routine. But Windows also includes a number of programming interfaces which are implemented as services that run as separate processes. Applications communicate with user-mode services through RPCs.

Unlike Linux, Windows is case insensitive, meaning it does not generally distinguish between upper- and lowercase.

Wine

Wine implements the Windows application binary interface (ABI) entirely in user space, rather than as a kernel module. Services normally provided by the kernel in Windows are provided by a daemon known as the wineserver, whose task is to implement basic Windows functionality, as well as integration with the X Window System, and translation of signals into native Windows exceptions.

Although Wine implements some aspects of the Windows kernel, it is not possible to use native Windows drivers with it, due to Wine's underlying architecture. This prevents certain applications and games from working, for example those using StarForce copy-protection which requires virtual device drivers to be installed.

Wine is primarily developed for Linux, but the macOS, FreeBSD, and Solaris (SPARC was dropped in 1.5.26) ports are currently (as of August 2013) well maintained, although a packaged file for Mac isn't available. Wine is also available for NetBSD and a number of other systems via pkgsrc. Since October 2010, Wine also works on the ARM platform when used as Winelib (which lets developers compile Windows code on Linux using Wine as a library). Some versions of Wine's DLLs are available for Microsoft Windows, but Wine does not fully compile or run on Windows yet.

User interface

Wine is usually invoked from the command-line interpreter: wine windowsprogram.exe. Additionally there is the utility program winecfg, which starts a graphical user interface.

Functionality

The developers of the Direct3D portions of Wine have continued to implement new features such as pixel shaders to increase game support. Wine can also use native DLLs directly, thus increasing functionality, but then a license for Windows is needed unless the DLLs were distributed with the application itself.

winecfg is a GUI configuration utility included with Wine. Winecfg makes configuring Wine easier by making it unnecessary to edit the registry directly, although, if needed, this can be done with the included registry editor (similar to Windows regedit). Wine also includes its own open-source implementations of several other Windows programs, such as notepad, wordpad, control, iexplore, and explorer.

The Wine Application Database (AppDB) is a community-maintained on-line database about which Windows programs works with Wine and how well they work.

Backward compatibility

Wine ensures good backward compatibility with legacy Windows applications, including those written for Windows 3.1x. Wine can mimic different Windows versions required for some programs, going as far back as Windows version 2.0. However, Windows 1.x and Windows 2.x support was removed from Wine development version 1.3.12. If DOSBox is installed on the system (see below on MS-DOS), Wine development version 1.3.12 and later nevertheless show the "Windows 2.0" option for the Windows version to mimic, but Wine still won't run most Windows 2.0 programs because MS-DOS and Windows functions are not currently integrated.

Backward compatibility in Wine is superior to that of Windows, as newer versions of Windows can force users to upgrade legacy Windows applications. In many cases, Wine can offer better legacy support than newer versions of Windows with "Compatibility Mode". Wine can run 16-bit Windows programs on a 64-bit operating system, which uses an x86-64 (64-bit) CPU. 64-bit versions of Microsoft Windows cannot run 16-bit Windows programs.

Wine partially supports Windows console applications, and the user can choose which backend to use to manage the console (choices include raw streams, curses, and user32). When using the raw streams or curses backends, Windows applications will run in a Unix terminal.

64-bit applications

Preliminary support for 64-bit Windows applications was added to Wine 1.1.10, in December 2008. This requires at least gcc version 4.4, and the Wine developers expect that it will take significant time before support stabilizes. However, as almost all Windows applications are currently available in 32-bit versions, and the 32-bit version of Wine can run on 64-bit platforms, this is seen as a non-issue.

The 64-bit port of Wine also has preliminary WoW64 support (as of April 2010), which allows both 32-bit and 64-bit Windows applications to run inside the same Wine instance.

Third-party applications

Some applications require more tweaking than simply installing the application in order to work properly, such as manually configuring Wine to use certain Windows DLLs. The Wine project does not integrate such workarounds into the Wine codebase, instead preferring to focus solely on improving Wine's implementation of the Windows ABI. While this approach focuses Wine development on long-term compatibility, it makes it difficult for users to run applications that require workarounds. Consequently, many third-party applications have been created to ease the use of those applications that don't work out of the box within Wine itself. The Wine wiki maintains a page of current and obsolete third-party applications.

Windows CE

Wine will not run Windows CE programs. There is an ongoing project to port Wine to ARM processors, which may in the future be used as a base for a WineCE running Windows CE programs. However, there is a pre-alpha proof-of-concept version of Wine that can run Windows CE programs called WineCE.

MS-DOS

Early versions of Microsoft Windows run on top of MS-DOS and Windows programs may depend on MS-DOS programs being runnable. Wine does not have good support for MS-DOS, but starting with development version 1.3.12, Wine tries running MS-DOS programs in DOSBox if DOSBox is available on the system. However, due to a bug, current versions of Wine incorrectly identify Windows 1.x and Windows 2.x programs as MS-DOS programs, attempting to run them in DOSBox (which does not work).

Compatibility for Internet Explorer

Internet Explorer can be installed directly on Wine. However, it is not recommended to do so, since (there is an alternative with Wine and) at least in the past it crashed or does not work well on recent versions of Wine which had poor support for Internet Explorer.

Internet Explorer 5 can be installed on Wine 1.3.9 but crashes frequently. Internet Explorer 5.5 is buggy on Wine 1.3.6, and Internet Explorer 6 refuses to install on Wine 1.6-rc5. Internet Explorer 7 32-bit version does not work very well on 1.5.11, and the 64-bit version does not load web pages on 1.6-rc5. Internet Explorer 8 also crashes constantly on Wine 1.6. Internet Explorer 9 (both 32-bit and 64-bit) and 10 cannot be installed.

An alternative for installing Internet Explorer directly is to use IEs4Linux. However, It is not compatible with the latest versions of Wine, and the development of IEs4Linux is still inactive.

Other versions of Wine

The core Wine development aims at a correct implementation of the Windows ABI as a whole and has sometimes lagged in some areas of compatibility with certain applications. Direct3D, for example, remained unimplemented until 1998, although newer releases have had an increasingly complete implementation.

CrossOver

CodeWeavers markets CrossOver specifically for running Microsoft Office and other major Windows applications, including some games. CodeWeavers employs Alexandre Julliard to work on Wine and contributes most of its code to the Wine project under the LGPL. CodeWeavers also released a new version called CrossOver Mac for Intel-based Apple Macintosh computers on 10 January 2007.

CrossOver now includes the functionality of both the CrossOver Games and CrossOver Pro lines therefore CrossOver Games and CrossOver Pro are no longer available as single products.

CrossOver Games was optimized for running Windows video games. Unlike CrossOver, it didn't focus on providing the most stable version of Wine. Instead, experimental features are provided to support newer games.

Cedega / WineX

TransGaming Technologies produced the proprietary Cedega software. Formerly known as WineX, Cedega represented a fork from the last MIT-licensed version of Wine in 2002. Much like CrossOver Games, TransGaming's Cedega was targeted towards running Windows video games. On 7 January 2011, TransGaming Technologies announced continued development of Cedega Technology under the GameTree Developer Program. TransGaming Technologies allowed members to keep using their Cedega ID and password until 28 February 2011.

Cider

TransGaming has also produced Cider, a library for Apple–Intel architecture Macintoshes. Instead of being an end-user product, Cider (like Winelib) is a wrapper allowing developers to adapt their games to run natively on Intel Mac without any changes in source code.

WINE@Etersoft

The Russian company Etersoft has been developing a proprietary version of Wine since 2006. WINE@Etersoft supports popular Russian applications (for example, 1C:Enterprise by 1C Company). For 2010, Etersoft was going to issue WINE@Etersoft CAD, which is oriented towards CAD systems such as AutoCAD, BricsCAD, and Compass-3D.

Darwine

Darwine is a port of the Wine libraries to Darwin and to macOS for both the PowerPC and Intel x86 architectures. All patches for x86 version were merged back into the main branch of Wine in 2009. Development on the PPC version was abandoned. Mike Kronenberg previously created the WineHelper for Darwine to add a GUI and macOS style app for interacting with Wine, which was later replaced by Winebottler. Darwine now provides macOS compatible packages compiled from the Wine repository.

Wine for Android

On 3 February 2013 at the FOSDEM talk in Brussels, Alexandre Julliard demonstrated an early demo of Wine running on Google's Android operating system.

Pipelight/wine-compholio

The Pipelight Team has produced a custom version of Wine that acts as a wrapper for Windows NPAPI plugins within Linux browsers. This tool permits Linux users to run Microsoft Silverlight, the Windows version of Adobe Flash, and the Unity web plugin, along with a variety of other NPAPI plugins. The project provides an extensive set of patches against the upstream Wine project, some of which occasionally get approved and added to upstream Wine.

Other projects using Wine source code

Other projects using Wine source code include:

Reception

The Wine project has received a number of technical and philosophical complaints and concerns over the years.

Security

Because of Wine's ability to run Windows binary code, concerns have been raised over native Windows viruses and malware affecting Unix-like operating systems. Wine can run most malware, but programs running in Wine are confined to the current user's privileges, restricting some undesirable consequences. For this reason the developers of Wine recommend never running it as the superuser. Malware research software such as ZeroWine runs Wine on Linux in a virtual machine, to keep the malware completely isolated from the host system.

Another security concern is when the implemented specifications are ill-designed and allow for security compromise. Because Wine implements these specs, it will also implement any security vulnerabilities they contain.

Wine vs. native Unix applications

A common concern about Wine is that its existence means that vendors are less likely to write native Linux, macOS, and BSD applications. As an example of this, it is worth considering IBM's 1994 operating system, OS/2 Warp. An article describes the weaknesses of OS/2 which killed it, the first one being:

OS/2 offered excellent compatibility with DOS and Windows 3.1 applications. No, this is not an error. Many application vendors argued that by developing a DOS or Windows app, they would reach the OS/2 market in addition to DOS/Windows markets and they didn't develop native OS/2 applications.

The Wine project itself responds to these complaints on one of its wiki pages:

For most people there remain a handful of programs locking them in to Windows. It's obvious there will never be a Microsoft Office ported to Linux, however older versions of programs like TurboTax won't be ported either. Similarly, there are tens of thousands of games and internal corporate applications which will never be ported. If you want to use Linux and rely on any legacy Windows application, something like Wine is essential... Wine makes Linux more useful and allows for millions of users to switch who couldn't otherwise. This greatly raises Linux marketshare, drawing more commercial and community developers to Linux.

Also, the Wine Wiki page claims that Wine can help break the chicken-and-egg problem for Linux on the desktop:

This brings us to the chicken and egg issue of Linux on the desktop. Until Linux can provide equivalents for the above applications, its market share on the desktop will stagnate. But until the market share of Linux on the desktop rises, no vendor will develop applications for Linux. How does one break this vicious circle?

Again, Wine can provide an answer. By letting users reuse the Windows applications they have invested time and money in, Wine dramatically lowers the barrier that prevents users from switching to Linux. This then makes it possible for Linux to take off on the desktop, which increases its market share in that segment. In turn, this makes it viable for companies to produce Linux versions of their applications, and for new products to come out just for the Linux market. This reasoning could be dismissed easily if Wine was only capable of running Solitaire. However, now it can run Microsoft Office, multimedia applications such as QuickTime and Windows Media Player, and even games such as Max Payne or Unreal Tournament 3. Almost any other complex application can be made to run well given a bit of time. And each time that work is done to add one application to this list, many other applications benefit from this work and become usable too. Have a look at our Application Database to get an idea on what can be run under Wine.

The use of Wine for gaming has proved specifically controversial in the Linux community, as some feel it is preventing, or at least hindering, the further growth of native Linux gaming on the platform.

Microsoft

Microsoft has not made public statements about Wine. However, the Microsoft Update software will block updates to Microsoft applications running in Wine. On 16 February 2005, Ivan Leo Puoti discovered that Microsoft had started checking the Windows Registry for the Wine configuration key and would block the Windows Update for any component. As Puoti noted, "It's also the first time Microsoft acknowledges the existence of Wine."