DOSEMU, stylized as dosemu, is a

compatibility layer In software engineering, a compatibility layer is an interface that allows binaries for a legacy or foreign system to run on a host system. This translates system calls for the foreign system into native system calls for the host system. With s ...

software package that enables

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 ...

operating systems (e.g.,

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few op ...

DR-DOS DR-DOS is a disk operating system for IBM PC compatibles, originally developed by Gary A. Kildall's Digital Research, Inc. and derived from Concurrent PC DOS 6.0, which was an advanced successor of CP/M-86. Upon its introduction in 198 ...

FreeDOS FreeDOS (formerly PD-DOS) is a free software operating system for IBM PC compatible computers. It intends to provide a complete MS-DOS-compatible environment for running Legacy system, legacy software and supporting embedded systems. FreeDOS ca ...

) and

application software Application software is any computer program that is intended for end-user use not operating, administering or programming the computer. An application (app, application program, software application) is any program that can be categorized as ...

to run atop

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 ...

x86 x86 (also known as 80x86 or the 8086 family) is a family of complex instruction set computer (CISC) instruction set architectures initially developed by Intel, based on the 8086 microprocessor and its 8-bit-external-bus variant, the 8088. Th ...

-based PCs (

IBM PC compatible An IBM PC compatible is any personal computer that is hardware- and software-compatible with the IBM Personal Computer (IBM PC) and its subsequent models. Like the original IBM PC, an IBM PC–compatible computer uses an x86-based central p ...

computers).

Features

It uses a combination of

hardware-assisted 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 with ...

features and high-level emulation. It can thus achieve nearly native speed for 8086-compatible DOS operating systems and applications on

compatible processors, and for

DOS Protected Mode Interface In computing, the DOS Protected Mode Interface (DPMI) is a specification introduced in 1989 which allows a DOS program to run in protected mode, giving access to many features of the new PC processors of the time not available in real mode. It w ...

(DPMI) applications on

compatible processors as well as on

x86-64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit extension of the x86 instruction set architecture, instruction set. It was announced in 1999 and first available in the AMD Opteron family in 2003. It introduces two new ope ...

processors. DOSEMU includes an 8086 processor emulator for use with real-mode applications in x86-64

long mode In the x86-64 computer architecture, long mode is the mode where a 64-bit operating system can access 64-bit instructions and registers. 64-bit programs are run in a sub-mode called 64-bit mode, while 32-bit programs and 16-bit protected mod ...

. DOSEMU is only available for

and

Linux systems (Linux 3.15 x86-64 systems cannot enter DPMI by default. This is fixed in 3.16). 140715 bugs.debian.org DOSEMU is an option for people who need or want to continue to use legacy DOS software; in some cases virtualisation is good enough to drive external hardware such as device programmers connected to the

parallel port In computing, a parallel port is a type of interface found on early computers ( personal and otherwise) for connecting peripherals. The name refers to the way the data is sent; parallel ports send multiple bits of data at once (paralle ...

. According to its manual, "dosemu" is a user-level program which uses certain special features of the Linux kernel and the 80386 processor to run DOS in a DOS box. The DOS box, relying on a combination of hardware and software, has these abilities: * Virtualize all input-output and processor control instructions * Supports the word size and addressing modes of the iAPX86 processor family's "real mode", while still running within the full protected mode environment * Trap all

and

BIOS In computing, BIOS (, ; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is a type of firmware used to provide runtime services for operating systems and programs and to perform hardware initialization d ...

system calls and emulate such calls as needed for proper operation and good performance * Simulate a hardware environment over which DOS programs are accustomed to having control. * Provide DOS services through native Linux services; for example, dosemu can provide a virtual hard disk drive which is actually a Linux directory hierarchy. 090430 dosemu.sourceforge.net * API-level support for Packet driver, 090430 prdownloads.sourceforge.net src/dosext/net/net/pktnew.c IPX,

Berkeley sockets A Berkeley ( BSD) socket is an application programming interface (API) for Internet domain sockets and Unix domain sockets, used for inter-process communication (IPC). It is commonly implemented as a library of linkable modules. It originated wi ...

(dosnet). src/dosext/net/net/ipx.c src/dosext/net/v-net/dosnet.c

References

External links

*
dosemu2
{{Virtualization software 1992 software DOS emulators Compatibility layers Linux emulation software

Features

See also

References

External links