DOSBOX(1)DOSBOX(1)NAMEdosbox - an x86/DOS emulator with sound/graphics
SYNOPSISdosbox [-fullscreen] [-conf configfile] [-lang langfile] [file] [-c
This manual page briefly documents dosbox, an x86/DOS emulator.
The optional file argument should be a DOS executable or a directory.
If it is a dos executable (.com .exe .bat) the program will run auto‐
matically. If it is a directory, a DOS session will run with the direc‐
tory mounted as C:.
A summary of options is included below.
Start dosbox in fullscreen mode.
Runs the specified command before running file. Multiple com‐
mands can be specified. Each command should start with -c
Start dosbox with the options specified in configfile.
Start dosbox with the language specified in langfile.
-exitdosbox will exit after running the program specified by file.
INTERNAL COMMANDSdosbox supports most of the DOS commands found in command.com. In addi‐
tion, the following extra commands are available:
MOUNT [-t type] [-size size] driveletter sourcedirectory [-aspi]
[-ioctl] [-usecd number] [-label drivelabel]
Program to mount local directories as drives inside dosbox.
The driveletter inside dosbox (eg. C).
The local directory you want to have inside dosbox.
Type of the mounted directory. Supported are: dir (stan‐
dard), floppy, cdrom.
Sets the size of the drive.
Sets the name of the drive to drivelabel. Needed on some
systems if the cd label isn't read correctly. Useful when
a program can't find its cdrom.
-aspi Forces to use the aspi layer. Only valid if mounting a
cdrom under Windows systems with an ASPI-Layer.
-ioctl Forces to use ioctl commands. Only valid if mounting a
cdrom under windows which support them (Win2000/XP/NT).
Forces to use SDL cdrom support for drive number. Number
can be found by -cd. Valid on all systems.
-cd Displays all detected cdrom drives and their numbers. Use
To mount your /home/dos/dosgames directory as C drive in dosbox:
mount c /home/dos/dosgames
Display the amount of free memory
CONFIG [-writeconf] [-writelang] file
Write the current configuration or language settings to file, which is
located on the local filesystem. Not a mounted drive in dosbox.
LOADFIX [-size] [programname] [parameters]
Program to eat up memory, Useful for old programs which don't expect
much memory to be free.
The name of the program which is executed after loadfix
eats up its memory.
Parameters given to the programname executable.
-size The amount of memory to eat up (in kb). Example -32, -64
-f Frees all memory eaten up by loadfix.
Configuration and language files use a format similar to Windows .ini
files. If a file named dosbox.conf is found in the current directory,
it will be automatically loaded.
ALT-ENTER Go full screen and back.
CTRL-F5 Save a screenshot.
CTRL-F6 Start/Stop recording sound output to a wave file.
CTRL-F7 Decrease frameskip.
CTRL-F8 Increase frameskip.
CTRL-F9 Kill dosbox.
CTRL-F10 Capture/Release the mouse.
CTRL-F11 Slow down emulation (Increase DOSBox Cycles).
CTRL-F12 Speed up emulation (Decrease DOSBox Cycles).
Note: Once you increase your DOSBox cycles beyond your com‐
puter's maximum capacity, it will produce the same effect as
slowing down the emulation. This maximum will vary from com‐
puter to computer, there is no standard.
Fast machine. My guess would be pentium-2 400+ to get decent
emulation of games written for an 286 machine. For protected
mode games a 1 Ghz machine is recommended and don't expect them
to run fast though!! Be sure to read the next section on how to
speed it up somewhat.
To run resource-demanding games
dosbox emulates the CPU, the sound and graphic cards, and some
other stuff, all at the same time. You can overclock dosbox by
using CTRL-F12, but you'll be limited by the power of your
actual CPU. You can see how much free time your true CPU has by
various utils (top). Once 100% of your real CPU time is used
there is no further way to speed up dosbox unless you reduce the
load generated by the non-CPU parts of dosbox.
Close every program but dosbox.
Overclock dosbox until 100% of your CPU is used.(CTR-+F12)
Since VGA emulation is the most demanding part of dosbox in
terms of actual CPU usage, we'll start here. Increase the number
of frames skipped (in increments of one) by pressing CRTL-F8.
Your CPU usage should decrease. Go back one step and repeat
this until the game runs fast enough for you. Please note that
this is a trade off: you lose in fluidity of video what you gain
While we hope that, one day, dosbox will run virtually all pro‐
grams ever made for the PC... we are not there yet. At present,
dosbox run on a 1.7 Gigahertz PC is roughly the equivalent of a
25MHz 386 PC. While the 0.60 release has added support for
"protected mode" allowing for more complex and recent programs,
but note that this support is early in development and nowhere
near as complete as the support for 386 real-mode games (or ear‐
lier). Also note that "protected mode" games need substantially
more resources and may require a much faster processor for you
to run it properly in dosbox.
Not all DOS programs work properly. dosbox will exit without
warning if an error occured.
The README in /usr/share/doc/dosbox
This manual page was written by Peter Veenstra <H.P.Veen‐
firstname.lastname@example.org> and James Oakley <email@example.com>,
for the Debian system (but may be used by others).
October 5, 2003 DOSBOX(1)