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DOSCMD(1) BSD General Commands Manual DOSCMD(1) NAME doscmd -- run a subset of real-mode DOS programs SYNOPSIS doscmd -23AbDEfGHIMOPRrtVvXxYz -c file -d file -i port[:cnt] -o port[:cnt] -S int -U int [cmd [args ...]] DESCRIPTION The doscmd utility can either emulate a subset of DOS and run the single command cmd args, or it can be used to emulate a PC and boot DOS, which allows it to run a larger variety of DOS applications. It should be noted that MS DOS 6.2 and higher appear to cause difficulties for doscmd. To boot DOS, either provide the -b flag or omit the cmd argument. If -b is specified, cmd and args are ignored. Although doscmd only provides a subset of DOS, it is sufficient to run a variety of programs, including, but not limited to, compilers, assemblers and linker-loaders. The various flags available to doscmd are: -2 Enable debugging traces of every trap to the doscmd emulator from the DOS program. Note that some traps are handled in the kernel and hence will not be traced. -3 Enable debugging of several lower level functions, such as chang- ing of interrupt vectors and initializing paths to logical drives. -A Enable tracing of all interrupts that pass into the emulator. This is the same as using the -S option with all 256 possible in- terrupt values. -b Attempt to boot DOS rather than emulate it. -c file Capture all output directed at the screen into file. Note that direct screen writes will not be captured. -C List MS-DOS calls emulated and their return values. -D Enable debugging of the disk and file operations. -d file Send the debug output to file instead of stderr. -E Enable debugging of the exec routines. -G Enable debugging of the video (graphics) routines. -H Enable tracing of half implemented calls. -I Enable tracing of all interrupts. Almost the same as -A except a few less traces are turned on. -i port[:cnt] Enable tracing of all inputs requested from the io port. If cnt is present, trace from port to port+cnt-1. -M Enable debugging of the memory operations. -O Direct the debugging output to stdout rather than stderr. -o port[:cnt] Enable tracing of all outputs requested from the io port. If cnt is present, trace from port to port+cnt-1. -p port[:cnt] Map the requested io port (with optional range up to to port+cnt-1) to the real hardware I/O port(s). This will likely require root privs to access them. -P Enable tracing of io port calls (such as inb, outb, etc). -R Enable debugging of the file redirect code. -r Use the raw keyboard and display. Pressing <CTRL-ALT-DEL> will cause doscmd to exit. This allows use of VGA graphics. -S int Enable tracing of the interrupt int. -t Attempt to do instruction level tracing. Some instructions con- fuse the trace. Pressing <CTRL-ALT-T> attempts to toggle the trace mode on and off. -U int Disable tracing of the interrupt int. Useful after -A or -I. -V Include register dumps when reporting unknown interrupts. -v Same as -AH -X Enable debugging of the XMS operations. -x Open an X11 window to display output. This enables a variety in- terrupts not available otherwise. This can be used with or with- out -b. -Y Enable debugging of the EMS operations. -z Cause doscmd to pause just prior to jumping to the DOS program. Very little use except for developing doscmd. When starting up, doscmd attempts to read a configuration file. First the file .doscmdrc in the current directory. If not found there, the $HOME directory is searched. If still not found, the file /etc/doscmdrc is used. In the configuration file, a comment is started with the # character. Blank lines are ignored. Non empty lines either are environment vari- ables or commands which configure devices. Any line which has an = be- fore any white space is considered to be an environment variable assign- ment and is added to the DOS environment. The rest of the lines are one of the following boot [A: | C:] Set the device to boot from. By default A: is first tried, if it is defined, and if that fails, C: is tried. assign [A-Z]: [-ro] path Assigns the BSD/OS directory path to be assigned as the specified drive. If the -ro flag is specified, it is a read only file sys- tem. These assignments will not take place when booting DOS until the /usr/libdata/doscmd/redir.com binary is run. assign lpt[0-4]: [direct] path [timeout] Attempt to assign the specified printer to path. If timeout is specified then use it as the length of time for no activity (in seconds) to indicate that the printer should be flushed. The de- fault is 30 seconds. The direct option should be set when path refers to a real printer. assign [A: | B:] [-ro] path density assign flop[01] [-ro] path density Assign the file path to be used as either the next available floppy or to the specified floppy. If -ro is specified the floppy will be read only. The density may be one of: 180 9 head 40 track single sided floppy 360 9 head 40 track double sided floppy 720 9 head 80 track double sided floppy 1200 15 head 80 track double sided floppy 1440 18 head 80 track double sided floppy 2880 36 head 80 track double sided floppy assign [C-Z]: [-ro] path [type | cyl head sec] [fdisk_tab] assign hard[01] [-ro] path [type | cyl head sec] [fdisk_tab] Assign the file path to be used as either the next available hard disk or to the specified hard disk. A disk's geometry can either be directly specified with cyl being the number of cylinders, head the number of heads and sec the number of sectors per track, or it can be one of the standard types specified by type (see below). The option fdisk_tab argument specifies file to use as the first sector of this disk. This can be useful for inserting a false fdisk table when path only refers to part of a disk. assign com[1-4]: path port irq Assign the tty or pty specified by path to be used as the speci- fied com port. Its base address will be emulated at port at in- terrupt specified by irq. This code is lightly tested and may not suit all needs. portmap port [count] Map the requested io port (with optional range up to to port+count-1) to the real hardware I/O port(s). This will likely require root privs to access them. setver command version Cause doscmd, when emulating DOS, to report version as the version number of DOS when called from the program named command. The format of version is the same as of the MS_VERSION variable de- scribed below. If not already assigned, C: will be assigned to the root directory (/) and the current directory for C: will be set to the actual current direc- tory. Note that this means that invocations such as: doscmd ../foo will not work as the C: directory will start with the current path. Also, the following environment variables will be defined if not already defined: COMSPEC=C:\COMMAND.COM PATH=C:\ PROMPT=DOS> The PATH variable is also used to find cmd. Like DOS, first cmd.com will be looked for and then cmd.exe. CONFIGURATION VARIABLES There are several variables in the .doscmdrc file which are internal to doscmd and do not actually get inserted into the DOS environment. These are: MS_VERSION The value of this variable is used to determine the version of DOS that should be reported by doscmd. Note that doscmd will not change the way it works, just the way it reports. By default this value is 410, which corresponds to MS DOS version 4.1. To change it to version 3.2 (the default in previous versions of doscmd) use the value of 320. X11_FONT The value of this variable determines the font used in an X window. The default font is vga, which is installed in /usr/libdata/doscmd/fonts. Add the line `xset fp+ /usr/libdata/doscmd/fonts' to your ${HOME}/.xsession or ${HOME}/.xinitrc to let the X server find it. FILE TRANSLATION The doscmd utility translates BSD/OS file names into DOS file names by converting to all upper case and eliminating any invalid character. It does not make any attempt to convert ASCII files into the <CR><LF> format favored in the DOS world. Use fconv(1) (part of the ports collection) or similar tools to convert ASCII files. DISK TYPES +-----------+-----------------+-------------+---------------+------------+ | Type | Cylinders | Heads | Sectors | Size | +-----------+-----------------+-------------+---------------+------------+ | 01 | 306 | 4 | 17 | 10MB | | 02 | 615 | 4 | 17 | 20MB | | 03 | 615 | 6 | 17 | 30MB | | 04 | 940 | 8 | 17 | 62MB | | 05 | 940 | 6 | 17 | 46MB | +-----------+-----------------+-------------+---------------+------------+ | 06 | 615 | 4 | 17 | 20MB | | 07 | 462 | 8 | 17 | 30MB | | 08 | 733 | 5 | 17 | 30MB | | 09 | 900 | 15 | 17 | 112MB | | 10 | 820 | 3 | 17 | 20MB | +-----------+-----------------+-------------+---------------+------------+ | 11 | 855 | 5 | 17 | 35MB | | 12 | 855 | 7 | 17 | 49MB | | 13 | 306 | 8 | 17 | 20MB | | 14 | 733 | 7 | 17 | 42MB | | 15 | 976 | 15 | 17 | 121MB | +-----------+-----------------+-------------+---------------+------------+ | 16 | 612 | 4 | 17 | 20MB | | 17 | 977 | 5 | 17 | 40MB | | 18 | 977 | 7 | 17 | 56MB | | 19 | 1024 | 7 | 17 | 59MB | | 20 | 733 | 5 | 17 | 30MB | +-----------+-----------------+-------------+---------------+------------+ | 21 | 733 | 7 | 17 | 42MB | | 22 | 733 | 5 | 17 | 30MB | | 23 | 306 | 4 | 17 | 10MB | | 24 | 925 | 7 | 17 | 53MB | | 25 | 925 | 9 | 17 | 69MB | +-----------+-----------------+-------------+---------------+------------+ | 26 | 754 | 7 | 17 | 43MB | | 27 | 754 | 11 | 17 | 68MB | | 28 | 699 | 7 | 17 | 40MB | | 29 | 823 | 10 | 17 | 68MB | | 30 | 918 | 7 | 17 | 53MB | +-----------+-----------------+-------------+---------------+------------+ | 31 | 1024 | 11 | 17 | 93MB | | 32 | 1024 | 15 | 17 | 127MB | | 33 | 1024 | 5 | 17 | 42MB | | 34 | 612 | 2 | 17 | 10MB | | 35 | 1024 | 9 | 17 | 76MB | +-----------+-----------------+-------------+---------------+------------+ | 36 | 1024 | 8 | 17 | 68MB | | 37 | 615 | 8 | 17 | 40MB | | 38 | 987 | 3 | 17 | 24MB | | 39 | 987 | 7 | 17 | 57MB | | 40 | 820 | 6 | 17 | 40MB | +-----------+-----------------+-------------+---------------+------------+ | 41 | 977 | 5 | 17 | 40MB | | 42 | 981 | 5 | 17 | 40MB | | 43 | 830 | 7 | 17 | 48MB | | 44 | 830 | 10 | 17 | 68MB | | 45 | 917 | 15 | 17 | 114MB | +-----------+-----------------+-------------+---------------+------------+ | 46 | 1224 | 15 | 17 | 152MB | +-----------+-----------------+-------------+---------------+------------+ INSTALLING DOS ON A PSEUDO DISK To install DOS on a pseudo hard disk under doscmd, do the following: 1 Create a .doscmdrc with at least the following: assign A: /dev/fd0.1440 1440 assign A: /dev/fd0.720 720 assign hard boot_drive 80 2 2 You may need to adjust the raw files for the A: drive to match your system. This example will cause the HD drive to be tried first and the DD drive second. Note that you should only use raw devices or files at this point, do not use a cooked device! (Well, it would probably be okay for a hard disk, but certainly not the floppy) boot_drive should be the file name of where you want your bootable image to be. The three numbers which follow 80 2 2 say that the drive will have 80 cylinders, 2 heads and 2 sectors per track. This is the smallest drive possible which still can have MS DOS 5.0 installed on it along with a config.sys and autoexec.bat file. You might want to create a larger boot drive. The file boot_drive must exist, so use the command touch to create it. 2 Insert a floppy disk into the A: drive which is bootable to MS-DOS and has the commands fdisk, format and sys on it. You should also copy the file redir.com onto the floppy by either mounting it with the msdos file system type or by using mtools (e.g., "mwrite redir.com a:"). 3 run doscmd. 4 At the > prompt type fdisk. 5 Select Create DOS partition or Logical Drive. 6 Select Create Primary DOS Partition. 7 Tell it how big to make it (Typically the whole drive. It is pretty tiny after all.) 8 Get out of FDISK by hitting <ESC> a few times. 9 doscmd may abort, if it does, start up doscmd again. 10 At the > prompt, type format c: and follow the instructions. 11 At the > prompt type sys c:. 12 Get out of doscmd. 13 Either remove the floppy from the drive or add the line boot C: to your .doscmdrc. 14 You should now be running DOS off of your new disk. You will prob- ably want both config.sys and an autoexec.bat file. To start with, you can say: > copy con: config.sys LASTDRIVE=Z ^Z > copy con: autoexec.bat @echo off redir.com ^Z 15 Quit doscmd. 16 You know have a bootable pseudo disk which will automatically call the magic redir program, which installs FreeBSD disks. To use them add lines to your .doscmdrc such as: assign D: /usr/dos assign P: -ro /usr/prb Note that you will not always be able to access every file due to naming problems. DIAGNOSTICS If doscmd encounters an interrupt which is unimplemented, it will print a message such as: Unknown interrupt 21 function 99 and exit. If doscmd emits the message X11 support not compiled in when supplied the -x switch, this support can be added by defining an environment variable X11BASE which points to the installed X Window System (normally /usr/X11R6) and then typing make install in the source directory (nor- mally /usr/src/usr.bin/doscmd). For this to work, the X programmer's kit must have been installed. AUTHORS Pace Willisson, Paul Borman HISTORY The doscmd program first appeared in BSD/386. BSD January 30, 1995 BSD
NAME | SYNOPSIS | DESCRIPTION | CONFIGURATION VARIABLES | FILE TRANSLATION | DISK TYPES | INSTALLING DOS ON A PSEUDO DISK | DIAGNOSTICS | AUTHORS | HISTORY
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