DOSEMU

DOSEMU, stylized as dosemu, is a compatibility layer software package that enables DOS operating systems (e.g., MS-DOS, DR-DOS, FreeDOS) and application software to run atop Linux on x86-based PCs (IBM PC compatible computers).

DOSEMU

DOSEMU Running on C:\
Original author(s)	DOSEMU Team
Initial release	September 3, 1992; 32 years ago (1992-09-03)[1]
Final release	1.4.0 / May 5, 2007; 18 years ago (2007-05-05)
Repository	sf.net/p/dosemu/code/
Operating system	Linux
Type	Compatibility layer
License	GPL
Website	www.dosemu.org

dosemu2

Preview release	2.0pre9 / 29 January 2022; 3 years ago (2022-01-29)
Repository	github.com/dosemu2/dosemu2
Website	dosemu2.github.io/dosemu2/

Features

It uses a combination of hardware-assisted virtualization features and high-level emulation. It can thus achieve nearly native speed for 8086-compatible DOS operating systems and applications on x86 compatible processors, and for DOS Protected Mode Interface (DPMI) applications on x86 compatible processors as well as on x86-64 processors. DOSEMU includes an 8086 processor emulator for use with real-mode applications in x86-64 long mode.

DOSEMU is only available for x86 and x86-64 Linux systems (Linux 3.15 x86-64 systems cannot enter DPMI by default. This is fixed in 3.16).^[2]

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. 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 DOS and BIOS 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.^[3]
• API-level support for Packet driver,^[4] IPX, Berkeley sockets (dosnet).^[5][6]

See also

• Free and open-source software portal

• Comparison of platform virtualization software
• Virtual DOS machine
• DOSBox
• Wine
• FreeDOS