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       dosbox - an x86/DOS emulator with sound/graphics


       dosbox   [-fullscreen]   [-startmapper]   [-noautoexec]   [-securemode]
       [-userconf] [-scaler scaler] [-forcescaler scaler]  [-conf  configfile]
       [-lang langfile] [file] [-c command] [-exit] [-machine machinetype]

       dosbox -version

       dosbox -editconf program

       dosbox -opencaptures program

       dosbox -printconf

       dosbox -eraseconf

       dosbox -resetconf

       dosbox -erasemapper

       dosbox -resetmapper


       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
       automatically.  If  it  is a directory, a DOS session will run with the
       directory mounted as C:\.

       For an introduction type INTRO inside dosbox.


       A summary of options is included below.

              Start dosbox in fullscreen mode.

              Start the internal keymapper on startup of dosbox. You  can  use
              it to change the keys dosbox uses.

              Skips the [autoexec] section of the loaded configuration file.

              Same as -noautoexec, but adds  -securemode at the end
              of AUTOEXEC.BAT (which in turn disables any changes to  how  the
              drives are mounted inside dosbox)

              Load  the  configuration  file  located  in  ~/.dosbox.  Can  be
              combined with the -conf option.

       -scaler scaler
              Uses  the  graphical  scaler  specified  by  scaler.   See   the
              configuration file for the available scalers

       -forcescaler scaler
              Similar  to  the  -scaler parameter, but tries to force usage of
              the specified scaler even if it might not fit.

       -c command
              Runs  the  specified  command  before  running  file.   Multiple
              commands  can  be  specified.  Each command should start with -c
              though. A command can be: an Internal Program, a DOS command  or
              an executable on a mounted drive.

       -conf configfile
              Start dosbox with the options specified in configfile. This file
              has a section in which you can put commands you wish to  execute
              on   startup.   Multiple  configfiles  can  be  present  at  the

       -lang langfile
              Start dosbox with the language specified in langfile.

       -exit  dosbox will close itself when the DOS program specified by  file

       -machine machinetype
              Setup  dosbox  to  emulate  a  specific  type of machine.  Valid
              choices  are:  hercules,  cga,  tandy,   pcjr,   ega,   vgaonly,
              svga_s3(default),   svga_et3000,   svga_et4000,   svga_paradise,
              vesa_nolfb, vesa_oldvbe.  The machinetype has influence on  both
              the videocard and the available soundcards.

              Output version information and exit. Useful for frontends.

       -editconf program
              calls  program  with  as first parameter the configuration file.
              You can specify this command more than once.  In  this  case  it
              will  move to second program if the first one fails to start.

       -opencaptures program
              calls  program  with  as   first  parameter  the location of the
              captures folder.

              prints the location of the default configuration file.

       -eraseconf, -resetconf
              removes the default configuration file.

       -erasemapper, -resetmapper
              removes  the  mapperfile  configured  in   the   clean   default
              configuration file.


       dosbox  supports  most  of  the  DOS  commands found in In
       addition, the following extra commands are available:

       MOUNT [-t  type]  [-size  size]  driveletter  sourcedirectory  [-ioctl]
              [-usecd number] [-label drivelabel] [-freesize freesize]

       MOUNT -cd

       MOUNT -u driveletter

       Program to mount local directories as drives inside dosbox.

                     The driveletter inside dosbox (eg. C).

                     The local directory you want to have inside dosbox.

              -t type
                     Type   of  the  mounted  directory.  Supported  are:  dir
                     (standard), floppy, cdrom.

              -size drivesize
                     Sets the size of the  drive.  See  the  examples  in  the
                     README for details.

              -freesize size_in_mb
                     Sets  the  amount  of  free space available on a drive in
                     MB’s. This is a more simple version of -size.

              -label drivelabel
                     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. If you  don’t  specify  a
                     label  and  no  lowlevel  support  is  selected (-usecd #
                     and/or -ioctl/aspi):

                     For win32: label is extracted from "Real Drive".

                     For Linux: label is set to NO_LABEL.

                     If you do specify a label this label will be kept as long
                     as the drive
                             is mounted. It will not be updated !!

              -ioctl Forces to use ioctl commands.

              -usecd number
                     Forces to use SDL cdrom support for drive number.  Number
                     can be found by -cd.

              -cd    Displays all detected cdrom drives and their numbers. Use
                     with -usecd.

              -u     Unmounts a mounted drive. Doesn’t work on virtual  Drives
                     (like Z:\)


       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

       CONFIG -securemode

       Write  the current configuration or language settings to file, which is
       located on the local filesystem. Not a mounted drive in dosbox.

                     Switchesdosbox to a more secure mode. In  this  mode  the
                     internal  commands  MOUNT,  IMGMOUNT and BOOT won´t work.
                     It´s not possible either to create a  new  configfile  or
                     languagefile  in  this  mode.  (Warning you can only undo
                     this mode by restarting dosbox.)

       The configuration file controls various settings of dosbox: The  amount
       of  emulated  memory,  the emulated soundcards and many more things. It
       futher allows acces to AUTOEXEC.BAT.

       The language file controls all visible ouput of the  internal  commands
       and the internal dos.  See the section FILES for more information.

       LOADFIX [-size] [programname] [parameters]

       LOADFIX -f

       Program  to  reduce  the  amount  of   memory available. 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
                     or -128

              -f     Frees all memory eaten up by loadfix.


       Make dosbox reread the  directory  structure.  Useful  if  you  changed
       something  on  a  mounted  drive  outside  dosbox.(CTRL-F4 does this as


       A utility to mount disk images and CD‐ROM images in dosbox.

       Read the README of dosbox for the full and correct syntax.


       Boot will start floppy images or hard disk images  independent  of  the
       operating  system  emulation offered by dosbox.  This will allow you to
       play booter floppies or boot to other operating systems inside  dosbox.

       Read the README of dosbox for the full and correct syntax.


       You  need to enable IPX networking in the configuration file of dosbox.
       All of the IPX  networking  is  managed  through  the  internal  dosbox
       program IPXNET. For help on the IPX networking from inside dosbox, type
       IPXNET HELP and the program will list out  the  commands  and  relevant

       Read the README of dosbox for the full and correct syntax.


       Keyb can change the keyboardlayout and the codepage used inside dosbox.

       Read the README of dosbox for the full and correct syntax.


       Configuration and language files use a format similar to  Windows  .ini
       files.   If no configfile is specified at the commandline, a file named
       dosbox.conf (if present  in  the  current  directory)  will  be  loaded
       automatically. If a configfile is specified at the commandline that one
       will be used instead. If no configfile is specified  or  found  in  the
       current  directory   then dosbox will load one from ~/.dosbox/. It will
       try to create one if there is none.


       ALT-ENTER   Go full screen and back.

       ALT-PAUSE   Pause emulation.

       CTRL-F1     Start the keymapper.

       CTRL-ALT-F5 Start/Stop creating a movie of the screen.

       CTRL-F4     Swap mounted disk‐image (Only used  with  imgmount).
                   Update directory cache for all drives!

       CTRL-F5     Save a screenshot.(png)

       CTRL-F6     Start/Stop recording sound output to a wave file.

       CTRL-ALT-F7 Start/Stop recording of OPL commands.

       CTRL-ALT-F8 Start/Stop the recording of raw MIDI commands.

       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).

       ALT-F12     Unlock speed (turbo button).

       These  are  the  default keybindings. They can be changed in the

       Saved/recorded files can be found  in  current_directory/capture
       (can  be changed in the configfile).  The directory has to exist
       prior to starting dosbox else nothing gets saved/recorded !

       Note:  Once  you  increase  your  dosbox  cycles   beyond   your
       computer’s  maximum capacity, it will produce the same effect as
       slowing  down  the  emulation.   This  maximum  will  vary  from
       computer 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.(CTRL-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 CTRL-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
       in speed.


       While  we  hope  that,  one  day,  dosbox will run virtually all
       programs 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 earlier). 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 occurred.


       The README in /usr/share/doc/dosbox


       This    manual    page    was    written   by   Peter   Veenstra
       <>       and       James       Oakley
       <>,  for  the Debian system (but may be used
       by others).

                                 Feb 26, 2010