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|  READ THIS FILE ALL THE WAY THROUGH BEFORE ATTEMPTING TO INSTALL FROTZ  |
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Frotz was originally written specifically for MS/PC DOS.  When it began
to be ported to other machines and operating systems, the DOS port
lagged behind.  Now it is more or less on par with Unix Frotz with the
conspicuous exception that Blorb is not entirely supported.  Blorb is
supported only as far as extracting a zcode file, but not for getting
audio and graphic data.  For now, only the old Infocom-style mechanism
for these are supported.

Sound is supported through Soundblaster compatible sound cards.  Graphic
levels from Hercules to MCGA and VGA are supported.

To compile DOS Frotz, you need one of following:

	* Borland Turbo C++ 3.00.  This is the latest version I'm aware
	  of that are capable of building 16-bit DOS applications. Turbo
	  C 2.01 may also work, but is untested.  Both of these may be
	  obtained from archive.org.

	* Open Watcom C 2.0 or later.  This application suite can be
	  installed to a DOS machine to directly compile Frotz there or
	  to a Linux machine to cross-compile Frotz for DOS. It may be
	  obtained from https://github.com/open-watcom/open-watcom-v2.

To compile in a DOS environment PC-DOS, MS-DOS or DR-DOS version 5.0 or
higher is required.  FreeDOS 1.2 and later will also work.  The earliest
version of PC-DOS or MS-DOS under which DOS Frotz will run is currently
unknown.  Real or virtualized hardware will work, including Virtualbox
and DOSBox.

DOS Frotz is currently built only as a 16-bit application.


===================================
Installing Borland Turbo C / C++ ||
===================================

If you already have a copy of Turbo C++ or Turbo C, follow the
instructions to install it on your DOS machine.  Fortunately Borland's
successor, Embarcadero Technologies, has released these compiler suites
as freeware.  They can be obtained from archive.org at
https://archive.org/details/TURBOC3_20180515 and
https://archive.org/details/msdos_borland_turbo_c_2.01.  Instruction
manuals can also be found there.

You'll want the Turbo C and TASM binary directories in your path.  This
is what I use under DOSBox:

	path=z:\;c:\bin;%PATH%;c:\tc;c:\tc\bin;c:\tasm\bin


===========================
Installing Open Watcom C ||
===========================

Visit https://github.com/open-watcom/open-watcom-v2/releases and go into
one of the recent builds.  Download ow-snapshot.tar.gz and open it into
$HOME/watcom/.  You can also download the source and build it yourself.

Once you have $HOME/watcom/ populated correctly, add this to your
.bashrc or .profile files or wherever you set this stuff:

	export WATCOM=$HOME/watcom

You will then need to add to your path which bin directory is
appropriate for your OS.

If you are running Linux on amd64, add this:
	export PATH=$PATH:$WATCOM/binl64

If you are running Linux on i386, add this:
	export PATH=$PATH:$WATCOM/binl

You will also want the Watcom tools binary directory in your path.  This
is what I use under DOSBox:

	path=z:\;c:\bin;%PATH%;C:\WATCOM

It doesn't look like cross-compiling is supported from any combination
of OS and architecture other than Linux on i386 or amd64.


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Compilation under DOS ||
========================

1.  On a Unix machine, prepare the source code for compilation on a DOS
    machine.

2.  Copy the source code into your DOS machine and configure the build.

3.  Compile Frotz.

Here we go!
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1.  On your Unix machine, do "make dos" in the Frotz distribution
    directory, either in the Git repository or a downloaded tar.gz
    archive.  This will create a directory named "snavig/" containing
    source code all set up for compilation.  Zip up this directory and
    get it into your DOS machine.  The zip file will easily fit onto a
    single 360K floppy.  Snavig requires the use of GNU sed, so if
    you're on macOS, BSD, or some other non-Linux platform; install GNU
    sed before proceeding.

2.  Back on the DOS machine, unzip the snavig archive into a directory
    on the hard drive.  Go into it and edit the file "defs.h".  This is
    where you can enable or disable features and adjust compile-time
    options.  Disabling features will result in a smaller executable and
    run faster, which can be very important if you want to use Frotz on
    an original IBM PC.

3.  If you're using Turbo C, type "tcbuild".  If you're using Open
    Watcom C, type "owbuild".  These batch files simply call "make -f
    makefile.tc" or "wmake -f makefile.ow".  After a couple minutes,
    Frotz will be compiled and ready for use.  To clean up after a
    build, type "tcbuild clean" or "owbuild clean".


=======================
Minimum Requirements ||
=======================

The minimum hardware and operating system requirements of DOS Frotz are
unknown.  It's fairly clear that the original IBM PC can run all Infocom
games at least up to V5.  Graphics or sound might be possible.

Please send me reports of what hardware and games work and what don't.
