Editing DOSBox

{{Infobox software
| name                 = DOSBox
| logo                 = DOSBox icon.png
| screenshot           = DOSBox screenshot.png
| caption              = DOSBox 0.74 running on [[Windows Vista]]
| developer            = Peter "Qbix" Veenstra, Sjoerd "Harekiet" van der Berg, Tommy "fanskapet" Frössman, Ulf "Finster" Wohlers
| programming language = [[C++]] <!-- There's not a single shread of C code in DOSBox's svn. -->
| released             = 2002-07-22
| operating system     = [[Windows]], [[macOS]], [[Linux]], [[Android (operating system)|Android]], [[Chrome OS]] ([[Gentoo Linux]]), [[AROS]], [[AmigaOS 4]], [[Amiga]], [[BeOS]], [[FreeBSD]], [[OpenBSD]], [[MorphOS]], [[OS/2]], [[RISC OS]], [[Solaris 10]]
| language             = English (but supports alternate keyboard layouts)
| genre                = [[Virtual machine]], [[emulator]]
| license              = [[GNU General Public License]]
| website              = [https://www.dosbox.com https://www.dosbox.com]
}}

'''DOSBox''' is an [[emulator]] [[computer program|program]] which emulates an [[IBM PC compatible]] computer running a [[DOS]] operating system. Many IBM PC compatible [[Graphics card|graphics]] and [[sound card]]s are also emulated. This means that original DOS programs (including [[PC game]]s) are provided with an environment in which they can run correctly, even though the modern computers have dropped support for that old environment.

==History==
DOSBox is [[free software]] written primarily in [[C++]] and distributed under the [[GNU General Public License]]. DOSBox has been downloaded over 34 million times since its release on [[SourceForge]] in 2002.

A number of usability enhancements have been added to DOSBox beyond emulating DOS. The added features include [[Virtual disk image|virtual hard drives]], [[peer-to-peer networking]], [[Screenshot|screen capture]] and [[screencasting]] from the emulated screen.

More than 8 years have passed between 2010's 0.74 and the 2018's latest version 0.74-2, "a maintenance release" made in preparation "for the upcoming 0.75 release, which will enter regression testing soon" . But throughout these years development has been ongoing in the SVN version. Forks such as DOSBox SVN Daum and DOSBox SVN-lfn provide additional features, which include support for [[save state]]s and [[long filename]]s (LFN), while others such as DosBox-X add emulation for Japanese systems like the [[NEC PC-98]] and increase compatibility with various [[Demoscene]] productions.

A number of vintage DOS games have been commercially re-released to run on modern operating systems by encapsulating them inside DOSBox.

== Features ==
DOSBox is a [[command-line]] program, configured either by a set of command-line arguments or by editing a [[plain text]] configuration file. For ease of use, several graphical [[front end processor (program)|front-ends]] have been developed by the user community.

A popular feature of DOSBox is its ability to capture [[screenshot]]s and record gameplay footage. The video is [[Data compression|compressed]] using the [[lossless compression|lossless]] ''Zip Motion Block Video'' codec. In its uncompressed state the footage is almost an exact replica of the actual program. The video recording feature was added in version 0.65. In earlier versions, one had to rely on custom modifications and a third-party screen recorder to record video, but the quality and emulator performance was generally very poor.

The DOSBox project has a policy of not adding features that aren't used by DOS games if they take significant effort to implement, are likely to be a source of bugs or portability problems, and/or impact performance. Perhaps the most common hardware feature of DOS-era PCs that the official version of DOSBox doesn't emulate is the [[parallel port]] that was used to connect printers. As an alternative, the [[PrintScreen]] function of modern OSs can be used to capture the output of DOSBox. For similar reasons, no support for [[long filename]]s and [[Ctrl-Break]] is added into official versions, though support for them is available in some unofficial enhanced SVN builds.

=== Hardware emulation ===
DOSBox is a full [[central processing unit|CPU]] emulator, capable of running DOS programs that require the CPU to be in [[real mode]] or [[protected mode]].  Other similar programs, such as [[DOSEMU]] or [[Virtual DOS machine|VDMs]] for Windows and OS/2, provide  [[compatibility layer]]s and rely on virtualization capabilities of the [[Intel 80386|386]] family processors. Since DOSBox can emulate its CPU by interpretation, the environment it emulates is completely independent of the host CPU. On systems which provide the [[i386]] [[instruction set]], however, DOSBox can use [[binary translation|dynamic instruction translation]] to accelerate execution several times faster than interpretive CPU emulation.{{citation needed |date=February 2017}} The emulated CPU speed of DOSBox is also manually adjustable by the user to accommodate for the speed of the systems DOS programs were originally written for.

DOSBox can emulate a wide range of graphics and sound hardware. Graphics emulation includes [[text mode]], [[Hercules Graphics Card|Hercules]], [[Color Graphics Adapter|CGA]] (including some composite modes and the 160x100x16 tweaked modes), [[Tandy 1000|Tandy]], [[Enhanced Graphics Adapter|EGA]], [[Video Graphics Array|VGA]] (including [[Mode X]] and other tweaks), [[VESA BIOS Extensions|VESA]], and full [[S3 Trio|S3 Trio 64]] emulation. Sound hardware that can be emulated includes the [[PC speaker]] (played back through the host's standard sound output, not its physical internal PC speaker), [[AdLib]], [[Gravis Ultrasound]], [[Tandy 1000|Tandy]], [[Sound Blaster|Creative Music System/GameBlaster]], [[Sound Blaster|Sound Blaster 1.x/2.0/Pro/16]], and [[Covox Speech Thing|Disney Sound Source]]. [[MIDI]] output through an emulated [[MPU-401]] interface is available if the host is equipped with a physical MIDI-Out connector or a suitable software MIDI synthesizer. ([[Roland MT-32|MT-32]]/[[Roland CM-32L|CM-32L]] emulation is included in unofficial enhanced builds, but not in the official source code repository due to need for copyrighted [[ROM image]]s.) Storage is handled by mapping (either through the configuration file or through a command within the emulator) a drive letter in the emulator to a directory, image file, floppy disk drive, or CDROM drive on the host. A permanently mapped Z: drive stores DOSBox commands and startup scripts.

Emulation of [[Voodoo Graphics|Voodoo]] cards is in development {{as of|2010|10|lc=y}}. This should give not only support for games that use the Glide API, but also provide Direct3D support to Win9x guests.

DOSBox, unlike many other emulators, can simulate [[peer-to-peer]] or [[Internet]]/[[Intranet]] networking. This includes [[modem]] simulation over [[Internet protocol suite|TCP/IP]], allowing for DOS modem games to be played over modern LANs or the Internet, and [[IPX]] network tunneling, which allows for old IPX DOS multiplayer games to be played as [[UDP/IP]] over modern [[LAN]]s or the Internet. [[Win32]] and Linux specific builds support direct [[serial port]] access. Some third-party patches also allow DOSBox to emulate an [[NE2000]]-class [[network interface card]] as a passthrough to the host computer's own network card, essentially allowing full internet connectivity (for example, using Windows 3.1 and [[Winsock|Trumpet Winsock]]) and web browsing using programs such as [[Netscape Navigator]], although this is more of a curiosity than a useful feature.

DOSBox is capable of timing-compatible implementation of the serial ports, which can enable older hardware and software dependent on serial port timing to work; however, some [[USB]] devices that are supported by the host OS can act as a replacement for older serial port devices when using the emulator.

=== OS emulation ===
DOSBox provides a high level emulation of the DOS and BIOS interrupts, and contains its own internal DOS-like [[Shell (computing)|shell]]. This means that it can be used without owning a license to any real DOS operating system. Most commands that are typically used in installer [[batch file]]s are supported, but many of the more advanced commands of later DOS versions (e.g. post-[[Windows 98]] DOS shells) are not. In addition to its internal shell, it also supports running image files of games and software originally intended to start without any [[operating system]]. The DOS emulation enables DOSBox to mount folders of the host OS as virtual drives.

It can also boot disk images with real DOS environments (e.g. [[MS-DOS]], [[IBM PC DOS|PC DOS]], [[DR-DOS]] or [[FreeDOS]]) as well as other operating systems. Since DOSBox is not optimized for this mode of operation, booting any real OS inside DOSBox entails the loss of the use of directory-based virtual hard drives and some other enhancements that aren't directly compatible with the way real operating systems access hardware. For the kinds of hardware (such as disk drive controllers and computer mice) that are almost always accessed by DOS-based games through DOS and/or through the BIOS and/or through a software driver, rather than through direct access to hardware registers, DOSBox generally provides no hardware-level emulation. This means that the direct use of copy-protected physical media or of floppy disks in non-standard formats is generally not possible from DOSBox.

=== Commands ===
The following list of [[command (computing)|commands]] is supported by DOSBox.

{{div col|colwidth=9em}}
* [[ATTRIB]]
* CALL
* [[cd (command)|CD]]
* [[cd (command)|CHDIR]]
* [[choice (command)|CHOICE]]
* [[cls (command)|CLS]]
* [[copy (command)|COPY]]
* [[del (command)|DEL]]
* [[del (command)|DELETE]]
* [[dir (command)|DIR]]
* [[echo (command)|ECHO]]
* [[del (command)|ERASE]]
* [[exit (command)|EXIT]]
* [[GOTO]]
* [[help (command)|HELP]]
* IF
* [[LOADHIGH|LH]]
* [[LOADHIGH]]
* [[mkdir|MD]]
* [[mkdir|MKDIR]]
* [[PATH (variable)|PATH]]
* [[Pause (DOS command)|PAUSE]]
* [[rmdir|RD]]
* [[Comment (computer programming)|REM]]
* [[ren (command)|REN]]
* [[ren (command)|RENAME]]
* [[rmdir|RMDIR]]
* [[Environment variable|SET]]
* SHIFT
* [[SUBST]]
* [[TYPE (DOS command)|TYPE]]
* [[ver (command)|VER]]
{{div col end}}

== Ports ==
DOSBox uses the [[Simple DirectMedia Layer|SDL]] library and has been [[porting|ported]] to many operating systems.  A port for [[Xbox (console)|Microsoft Xbox]] (called DosXbox) was released in 2004. Using the [[DOS extender#DOS extenders|HX DOS Extender]], it can even run in [[DOS]]. The source code has also been [[Fork (software development)|fork]]ed to provide compatibility on a number of non-[[x86]] PC computer platforms, including the [[Palm OS]], [[PlayStation Portable]], [[Android (operating system)|Android]], [[iOS]], [[Symbian]], [[Maemo]], [[BlackBerry PlayBook]], [[Wii]], and the [[GP2X]], on various [[computing architecture]]s including [[PowerPC]], [[SPARC]], [[MIPS architecture|MIPS]] and [[ARM architecture|ARM]]. DOSBox is included in the software repositories of many [[Linux distributions]] such as [[Fedora (operating system)|Fedora]], [[Debian]], and [[Ubuntu (operating system)|Ubuntu]]. There is also a port to [[Google Native Client]] called NaClBox, a port to [[Java applet]]s called jDosbox, and a port of jDosBox to [[Google Web Toolkit|GWT]] (using the [[Canvas element]]) called jsDOSBox.

=== DOSBox and the Wine compatibility layer ===
Starting with version 1.3.12, the developers of the [[Wine (software)|Wine]] [[compatibility layer]] have begun the process of integrating DOSBox into Wine to facilitate running DOS programs that are not supported natively by the Wine [[Virtual DOS machine]] (winevdm).

== Usage ==

=== Commercial deployment ===
[[id Software]] has used DOSBox to re-release vintage games such as ''[[Wolfenstein 3D]]'' and ''[[Commander Keen]]'' on [[Valve Corporation|Valve]]'s [[Steam (software)|Steam]]. In the process, it was reported they violated the program's license, the GNU GPL; the breach, which was reported as an oversight, was promptly resolved. [[Activision Blizzard]] has also used it to re-release [[Sierra Entertainment]]'s DOS games.<!--   --> [[LucasArts]] used it to re-release ''[[Star Wars: Dark Forces]]'' for modern machines on Steam. [[2K Games]] producer Jason Bergman stated the company used DOSBox for Steam re-releases of certain parts of the [[X-Com]] series. [[GOG.com]] uses DOSBox for some of their DOS releases. [[Bethesda Softworks]] recommends DOSBox and  provides a link to the DOSBox website on the downloads page for ''[[The Elder Scrolls: Arena]]'' and ''[[The Elder Scrolls II: Daggerfall]]''.  Bethesda also included DOSBox with both games in The Elder Scrolls Anthology release. [[3D Realms]] also recommends DOSBox and, like Bethesda Softworks, provides a link to the DOSBox website on their downloads page.

[[Electronic Arts]] uses DOSBox for some of their classic games on their [[Origin (digital distribution software)|Origin]] client like [[Wing Commander III]], [[Crusader: No Remorse]], and [[SimCity 2000]].

[[dBase LLC]] utilizes DOSBox in their [[dbDOS]] product since 2012.

=== Non-commercial notable uses ===
Since 23 December 2014, the [[Internet Archive]] hosts a browser-based version of DOSBox (converted to [[JavaScript]] using [[Emscripten]]) with thousands of playable [[PC game]]s. The collection is provided for "scholarship and research purposes only".

[[Category:Emulators]]