fdbox

A new command interpreter for FreeDOS. Code will contain usable utilities borrowed from Unix and maintain (basic) compatibility with MSDOS 6.22 command.com, while (sometimes) improving.

The program compiles also as a native Linux executable

.. and Windows as well

.. and Apple silicon as well

Yes this code compiles on DOS 8086 16bit, Windows 8086 32bit and Linux amd64 and OSX64/ARM!. I see no reasons why should it fail to compile on other platforms/OS.

Status

• Only DOS commands are supported. Unix commands might follow.
• Code compiles using clang/GCC (Windows+Linux+OSX), TCC (DOS), OpenWatcom2/snapshot (DOS).
• Github actions compiles all the code for Linux, Windows, MSDOS and OSX, the workflow also runs the test on all platforms. (tests do not run on MSDOS yet).
• Currently, code uses LibC's functions - so it is limited to standard C code support for localization.
• All commands support multiple arguments (like Unix shells), unlike DOS which you cannot do del /r file1.txt *.bat /f, and arguments can come even after file names (not only at the beginning of the command).
• Some commands share the same code (copy+move, date+time)
• Interactive shell is being worked on. I want to have 4DOS command
  completion, or bash/zsh.
• Contains a bash shell script to generate the development environment for DOS+DosBOX.

See also:

• coding.md
• building.md
• readme.txt

TODO

• Command (main interactive shell) does not support batch files. See https://github.com/elcuco/fdbox/tree/batch-files-support branch.
• Command does not support redirection
• Command does not support "|"
• TurboC does need a proper makefile.
• Make OW build a Windows binary (as well)
• OW build is done by using gnu-make and not ow-make
• Setup CI/CD to compile a DJGPP cross compilation
• Setup CI/CD to run dosemu in console mode, and compile using TC
• Setup CI/CD to run dosemu in console mode, and run tests
• History is not saved/read.
• I had this configure system which would create the sources for commands and auto generate the applets.c file. Not against the idea.
• There are commands that are available on Unix and DOS, but differ in syntax unsure how to handle.
• MSDOS: Using XMS swapping would be good, using SPWNO would be epic (http://www.cs.cmu.edu/%7Eralf/files.html)
• Platform specific APIs (& on Windows/Linux to run a program in background for example).
• On Linux we can print escape sequences to make files on dir be clickable.
• see also implementation tables bellow

Implementation status of commands

command	status	remark
beep	done	needs to be tested on DOS/Windows, on unix it just beeps
call	not yet
cd	done
cls	done
copy	WIP	All copies are binaries. By design. Recursive copy not implemented yet Copy globs, and several files - not implemented yet Append files (copy file1+file2 file3) not implemented yet
command	WIP	See bellow
date/time	WIP	Missing AM/PM support Not supported on windows (only DOS/Linux)
del	done	Prompt might need more testing
dir	WIP	/o? order is funky. /p - pausing is not implemented Missing disk usage
echo	done
if	done
for	not yet
md/mkdir	done
move/rename/ren	done	All these command are aliases, hardcoded
prompt	done	internal library issues
rem	done
set	done
type	done	Bonus: support also line numbers printing
type	done	As a bonus, can also print line numbers
ver	done

Major project worked on is interactive shell. The main task right now is the internal readline code (history, editor etc).

Command line editor status:

Key	status	remark
Left/right/home/end	done
Up/Down: history	WIP	fails randomly
Backspace	done
Del	not yet
control+a : HOME	done
control+b : word left	not yet
control+c : cancel	WIP	de facto - clear line, fails on Posix
control+d : EOF	done
control+e : END	done
control+f : word right	not yet
control+l : cls	done
TAB	not yet
insert/override	done	Cursor shape not supported on OXS
esc	????	Fix breaks on Linux/OSX ?
insert	done	Toggle insert/override mode
control+arrows	not yet	move to next/prev word

Compiler support

1. Linux: Clang/GCC - this is the main development environment. Supported.
2. Windows10: MinGW/TCM (9,10) - this is the main development environment. Supported.
3. DOS: TC 2.02 - this is the main development environment. Supported.

   BUG:

   glob() functionality tends to allocate too much >memory, and the code is faulty, not reporting this to the app. Results in garbage in the screen when dir on a directory with lots of files (~80 on my tests, but it depends on memory available).

4. DOS/OpenWatcom (WIP): we have a CI building it. The generated binary crashes on startup.
5. OSX: Works (similar code path as Linux)
6. DOS: DJGPP - I am having problems in runtime. Seems like tolower() is breaking my code. Might be a compiler bug. Interactive shell segfaults.
7. DOS: PacificC - It's not a high priority, but we have a working branch called pacific-c-support which contains the work needed to make this project compile with that compiler.

Why?

Because.

I started this project at 2001, and only recently re-started it from scratch. The idea came after I saw Minibox, and though (as every programmer does...) "this is wrong, this is not the way to do this, I will do it better". I am unsure if I am doing it better, but this is the best way to thank Ercan Ersoy - you give me a push to restart this project: thank you.

My old project: http://dgi_il.tripod.com/fds/index.html

Minibox: https://github.com/ercanersoy/Minibox

Ideas and inspiration do come from busybox (the applet concept for example). However - this project does not share any code, and cannot be considered a derived work (please don't copy code from Busybox here, as I might re-license code, and want new implementations for those old ideas).

DosBox setup

I created a Linux shell script which will populate a "C:" drive for development. Just execute it, and it will download all the compilers, and create an AUTOEXEC.BAT. Do this inside the etc directory.

Then in DosBox config, edited the start-up files (usually at the end) to this:

mount c /home/diego/fdbox/etc/dosbox
mount d /home/diego/fdbox/
C:\AUTOEXEC.BAT
d:

Then, each time I start dosbox, I have in the path all the compilers I need, and I am redirected to the full code of the program in drive D:. The project contains a TurboC project file - so typing tc will bring up the IDE with the project ready to hack.

Similar setup can be done from the GUI of DOSBOX-X, it just needs more clicks.

Linux's requirements (on Ubuntu I found that I need p7zip-full instead of 7z:

apt install 7z wget dosbox

OSX requirements:

brew install p7zip wget dosbox

Windows:

• Download 7zip, the script will only look in default location
• You can run this script from Github's bash (use official git for windows install)

TODO: If you save a file under DOS, DosBox will rename it to capital letters. I am unsure how to automatically do this.

License

GPL V3. See file license.txt