Binary-code compatibility (binary compatible or object-code compatible) is a property of a

computer system A computer is a machine that can be programmed to automatically carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic sets of operations known as ''programs'', wh ...

, meaning that it can run the same

executable code In computer science, executable code, an executable file, or an executable program, sometimes simply referred to as an executable or binary, causes a computer "to perform indicated tasks according to encoded instructions", as opposed to a d ...

, typically

machine code In computer programming, machine code is computer code consisting of machine language instructions, which are used to control a computer's central processing unit (CPU). For conventional binary computers, machine code is the binaryOn nonb ...

for a general-purpose computer

central processing unit A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary Processor (computing), processor in a given computer. Its electronic circuitry executes Instruction (computing), instructions ...

(CPU), that another computer system can run. Source-code compatibility, on the other hand, means that recompilation or interpretation is necessary before the program can be run on the compatible system. For a compiled program on a general operating system, binary compatibility often implies that not only the CPUs ( instruction sets) of the two computers are binary compatible, but also that interfaces and behaviours of the

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

(OS) and

application programming interface An application programming interface (API) is a connection between computers or between computer programs. It is a type of software Interface (computing), interface, offering a service to other pieces of software. A document or standard that des ...

s (APIs), and the

application binary interface An application binary interface (ABI) is an interface exposed by software that is defined for in-process machine code access. Often, the exposing software is a library, and the consumer is a program. An ABI is at a relatively low-level of a ...

s (ABIs) corresponding to those APIs, are sufficiently equal, i.e. "compatible". A term like backward-compatible usually implies object-code compatibility. This means that newer computer hardware and/or software has (practically) every feature of the old, plus additional capabilities or performance. Older executable code will thus run unchanged on the newer product. For a compiled program running directly on a CPU under an OS, a "binary compatible operating system" primarily means

(ABI) compatibility with another system. However, it also often implies that APIs that the application depends on, directly or indirectly (such as the

Windows API The Windows API, informally WinAPI, is the foundational application programming interface (API) that allows a computer program to access the features of the Microsoft Windows operating system in which the program is running. Programs can acces ...

, for example), are sufficiently similar. Hardware (besides the CPU, such as for graphics) and peripherals that an application accesses may also be a factor for full compatibility, although many hardware differences are hidden by modern APIs (often partly supplied by the OS itself and partly by specific

device driver In the context of an operating system, a device driver is a computer program that operates or controls a particular type of device that is attached to a computer or automaton. A driver provides a software interface to hardware devices, enabli ...

s). In other cases, a general

porting In software engineering, porting is the process of adapting software for the purpose of achieving some form of execution in a computing environment that is different from the one that a given program (meant for such execution) was originally desig ...

of the software must be used to make non-binary-compatible programs work. Binary compatibility is a major benefit when developing computer programs that are to be run on multiple OSes. Several

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

-based OSes, such as

FreeBSD FreeBSD is a free-software Unix-like operating system descended from the Berkeley Software Distribution (BSD). The first version was released in 1993 developed from 386BSD, one of the first fully functional and free Unix clones on affordable ...

NetBSD NetBSD is a free and open-source Unix-like operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was fork (software development), forked. It continues to ...

, offer binary compatibility with more popular OSes, such as

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

-derived ones, since most binary executables are not commonly distributed for such OSes. Most OSes provide binary compatibility, in each version of the OS, for most binaries built to run on earlier versions of the OS. For example, many executables compiled for Windows 3.1,

Windows 95 Windows 95 is a consumer-oriented operating system developed by Microsoft and the first of its Windows 9x family of operating systems, released to manufacturing on July 14, 1995, and generally to retail on August 24, 1995. Windows 95 merged ...

Windows 2000 Windows 2000 is a major release of the Windows NT operating system developed by Microsoft, targeting the server and business markets. It is the direct successor to Windows NT 4.0, and was Software release life cycle#Release to manufacturing (RT ...

can also be run on

Windows XP Windows XP is a major release of Microsoft's Windows NT operating system. It was released to manufacturing on August 24, 2001, and later to retail on October 25, 2001. It is a direct successor to Windows 2000 for high-end and business users a ...

Windows 7 Windows 7 is a major release of the Windows NT operating system developed by Microsoft. It was Software release life cycle#Release to manufacturing (RTM), released to manufacturing on July 22, 2009, and became generally available on October 22, ...

, and many applications for

DOS DOS (, ) is a family of disk-based operating systems for IBM PC compatible computers. The DOS family primarily consists of IBM PC DOS and a rebranded version, Microsoft's MS-DOS, both of which were introduced in 1981. Later compatible syste ...

ran on much newer versions of Windows up to Windows 10 for as long as the

NTVDM Virtual DOS machines (VDM) refer to a technology that allows running 16-bit/32-bit DOS and 16-bit Windows programs when there is already another operating system running and controlling the hardware. Overview Virtual DOS machines can operate e ...

was supported.

Binary compatible hardware

For a digital processor implemented in hardware, binary compatibility means that (a large subset of)

produced for another processor can be correctly executed and has (much) the same effect as on the other processor. This is quite common among many processor families, although it is rather uncommon among the ubiquitous small

embedded system An embedded system is a specialized computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is e ...

s built around such processors. Full machine code compatibility would here imply exactly the same layout of interrupt service routines, I/O-ports,

hardware register In digital electronics, especially computing, hardware registers are circuits typically composed of flip-flops, often with many characteristics similar to memory, such as: * Using an memory or port address to select a particular register in a ma ...

s, counter/timers, external interfaces and so on. For a more complex embedded system using more

abstraction layer In computing, an abstraction layer or abstraction level is a way of hiding the working details of a subsystem. Examples of software models that use layers of abstraction include the OSI model for network protocols, OpenGL, and other graphics libra ...

s (sometimes on the border to a general computer, such as a mobile phone), this may be different.

Binary compatible operating systems

Binary compatible operating systems are OSes that aim to implement binary compatibility with another OS, or another variant of the same brand. This means that they are ABI-compatible (for

). As the job of an OS is to run programs, the

instruction set architecture In computer science, an instruction set architecture (ISA) is an abstract model that generally defines how software controls the CPU in a computer or a family of computers. A device or program that executes instructions described by that ISA, ...

s running the OSes have to be the same or compatible. Otherwise, programs can be employed within a CPU emulator or a faster dynamic translation mechanism to make them compatible. For example, the

Linux kernel The Linux kernel is a Free and open-source software, free and open source Unix-like kernel (operating system), kernel that is used in many computer systems worldwide. The kernel was created by Linus Torvalds in 1991 and was soon adopted as the k ...

is not compatible with Windows. This does not mean that Linux cannot be binary compatible with Windows applications. Additional software,

Wine Wine is an alcoholic drink made from Fermentation in winemaking, fermented fruit. Yeast in winemaking, Yeast consumes the sugar in the fruit and converts it to ethanol and carbon dioxide, releasing heat in the process. Wine is most often made f ...

, is available that does that to some degree. The

ReactOS ReactOS is a Free and open-source software, free and open-source operating system for i586/amd64 personal computers that is intended to be binary-code compatibility, binary-compatible with computer programs and device drivers developed for Wind ...

development effort seeks to create an

open-source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

free software Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...

OS that is binary compatible with Microsoft's

Windows NT Windows NT is a Proprietary software, proprietary Graphical user interface, graphical operating system produced by Microsoft as part of its Windows product line, the first version of which, Windows NT 3.1, was released on July 27, 1993. Original ...

family of OSes using Wine for application compatibility and reimplementing the Windows kernel for additional compatibility such as for drivers whereas Linux would use Linux drivers, not Windows drivers.

and other members of the

BSD The Berkeley Software Distribution (BSD), also known as Berkeley Unix or BSD Unix, is a discontinued Unix operating system developed and distributed by the Computer Systems Research Group (CSRG) at the University of California, Berkeley, beginni ...

family have binary compatibility with the

in usermode by translating Linux system calls into BSD ones. This enables the application and libraries code that run on

-based OSes to be run on BSD as well. Note that a binary compatible OS is different from running an alternative OS through

virtualization In computing, virtualization (abbreviated v12n) is a series of technologies that allows dividing of physical computing resources into a series of virtual machines, operating systems, processes or containers. Virtualization began in the 1960s wit ...

or emulation, which is done to run software within the alternative OS in the case when the host OS is not compatible. Sometimes virtualization is provided with the host OS (or such software can be obtained), which effectively makes the host OS compatible with programs. For example, Windows XP Mode for

allows users to run a

64-bit In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit central processing units (CPU) and arithmetic logic units (ALU) are those that are based on processor registers, a ...

version of Windows 7 and enable old software to still work in a

32-bit In computer architecture, 32-bit computing refers to computer systems with a processor, memory, and other major system components that operate on data in a maximum of 32- bit units. Compared to smaller bit widths, 32-bit computers can perform la ...

virtual machine running

;

VMware Workstation VMware Workstation Pro (known as VMware Workstation until release of VMware Workstation 12 in 2015) is a hosted (Type 2) hypervisor that runs on x64 versions of Windows and Linux operating systems. It enables users to set up virtual machines (VM ...

VMware Fusion VMware Fusion is a software hypervisor developed by VMware for macOS systems. It allows Macs with Intel or Apple M series CPUs to run virtual machines with guest operating systems, such as Microsoft Windows, Linux, or macOS, within the host m ...

, Parallels Workstation, and

Windows Virtual PC Virtual PC is a discontinued x86 emulator software for Microsoft Windows hosts and PowerPC-based Mac hosts. It was created by Connectix in 1997 and acquired by Microsoft in 2003, after which the program was renamed Microsoft Virtual PC. In ...

allow other OSes to be run on Windows, Linux, and macOS. For another example,

Mac OS X macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

on the

PowerPC PowerPC (with the backronym Performance Optimization With Enhanced RISC – Performance Computing, sometimes abbreviated as PPC) is a reduced instruction set computer (RISC) instruction set architecture (ISA) created by the 1991 Apple Inc., App ...

had the ability to run

Mac OS 9 Mac OS 9 is the ninth and final major release of the classic Mac OS operating system for Macintosh computers, made by Apple Computer. Introduced on October 23, 1999, it was promoted by Apple as "The Best Internet Operating System Ever", highlight ...

and earlier application software through

Classic A classic is an outstanding example of a particular style; something of Masterpiece, lasting worth or with a timeless quality; of the first or Literary merit, highest quality, class, or rank – something that Exemplification, exemplifies its ...

—but this did not make Mac OS X a binary compatible OS with Mac OS 9. Instead, the Classic environment was actually running Mac OS 9.1 in a

virtual machine In computing, a virtual machine (VM) is the virtualization or emulator, emulation of a computer system. Virtual machines are based on computer architectures and provide the functionality of a physical computer. Their implementations may involve ...

, running as a normal process inside of Mac OS X.

References

External links

KDE Techbase Policies
– a compendium of C++ development rules of thumb (wit
some examples
for not breaking binary compatibility between releases of a library.
ABI Analysis Tools
a set of open-source tools for analysis of ABI and backward binary compatibility implementing KDE Techbase Policies {{Application binary interface Backward compatibility Computing terminology de:Kompatibilität (Technik)#Binärkompatibilität

Binary compatible hardware

Binary compatible operating systems

See also

References

External links