Notes on the OS/2 implementation of dmake:
==========================================

As shipped the DOS versions of dmake will run under OS/2 protected mode.
However, support for a full OS/2 version is also provided.  The OS/2 version
will run in parallel under OS/2.  The port was made possible by files supplied
by:

   Duncan Booth   -- (duncanb@ibmpcug.co.uk, Bix:jrichards)
   Kai Uwe Rommel -- (rommel@lan.informatik.tu-muenchen.dbp.de),

For which I am grateful.  I have taken the two ports and integrated them
into a single port using the structure supplied by Duncan Booth, and some
files and OS2'ism supplied by Kai Rommel.

If there are any problems with the port then please let myself or one of the
two people above know.  I will then attempt to fix the problem.  I do not
have access to an OS/2 box to verify any problems myself.


Bootstrapping the binary:
-------------------------
   A make.cmd file is provided to bootstrap the binary.  The file contains
   several targets for bootstrapping.  Invoking the batch file with no
   arguments lists the possibilities shown below.

      INDEX:  You must specify one of:
	 msc40    - Microsoft C 4.0 compile.
	 msc50    - Microsoft C 5.0 compile.
	 msc51    - Microsoft C 5.1 compile.
	 msc60    - Microsoft C 6.0 compile.
	 ibm	  - IBM C2 compile.

   Based on the compiler you have installed and whether or not you
   want the swapping version of dmake, you should select the appropriate
   target and issue 'make.cmd target'.

   The command file runs a second command script that comes with the
   distribution which compiles the sources using the appropriate compiler and
   flags.  The MSC Versions of the batch files should not require any further
   user intervention during the compile.

   By default the command files make an executable that will run on an 8088
   cpu and up.  You can change that by making the initial version and then
   editing the config.mk file found in os2/mscdos and selecting a diferrent
   cpu type by supplying the appropriate compiler flags.
   You then need to remake dmake again but this time use dmake itself,
   see below.


Using dmake to Make itself:
---------------------------
   If you use dmake to make itself you must first set a number of makefile
   control variables, either through the environment or on the command line.

   The following variables must be set:

	OS	       - defines operating system (must be set)
	OSRELEASE      - particular version of it.
	OSENVIRNOMENT  - more customization (not needed for OS/2)

   These three variables should be defined in your environment.  Valid values
   for them are listed in the dmake makefile.mk file.  For example, if you
   are using OS/2, with Microsoft-C then the valid settings are:

	set OS=os2
	set OSRELEASE=mscdos

   dmake searches for an initial startup file, you should set the environment
   variable MAKESTARTUP to contain the full path to the startup file, eg:

	set MAKESTARTUP=\init\dmake.ini

   The dmake makefile has several variables that can be user specified and
   default to reasonable values if not set.

	MODEL   - defines the model to compile, valid values are
		  {s,c,m, or l}, defaults to 'l' (ie. large) model
		  if unspecified.

	MSC_VER - defines the version of Microsoft C in use, should be set to
		  one of 4.0, 5.0, 5.1 or 6.0; defaults to 6.0.

	DEBUG   - If set to '1' then make the debugging version of dmake, this
		  will also set MODEL to 'l'.

   To set the above variables you must specify them on the dmake command line
   or insert them into the makefile.mk script.



OS/2 Specifics
--------------

   There is a small number of OS/2 specific features that need to be
   stated.

   1. The environment variables TMP as well as TMPDIR are checked for the
      location of the directory where dmake should place any temporary files.
      TMPDIR is checked before TMP.

   2. Appropriate limits are setup for MAXPROCESSES and buffer sizes etc.
      See output of 'dmake -V'.

   3. By default dmake will look for the startup.mk file in the path:

	  $(INIT)/dmake.ini

      This is more in keeping with OS/2 philosophy.  You may still rename
      and put it anywhere else you like by defining the MAKESTARTUP
      environment variable.

   4. The OS/2 directory contains files required by Kai Rommel's compiler
      shell.  However you do not need the compiler shell to build dmake.

   5. Swapping the dmake binary to disk is not supported under OS/2.


Other notes:
------------
   dmake does not care if you are running cmd.exe or some other command
   interpretter, you must however specify the proper values of the environment
   variables SHELL, SHELLFLAGS, GROUPSHELL, and GROUPFLAGS in order for things
   to work correctly.  Read the man page first.

   Group recipes under OS/2 that use cmd.exe as the command interpretter
   require you to set the GROUPSUFFIX macro.

   As shipped the startup.mk files try to figure out what
   command interpretter you are using and set things up appropriately.
   Two command interpretters are supported in the shipped startup.mk file,
   cmd.exe (via COMSPEC), and the MKS Korn shell.

   dmake does not contain any builtin commands.  It gets all commands it
   executes from an external file system.  It is therefore most useful if it
   is used in conjunction with an environment similar to that provided by
   the MKS Tool kit, or equivalent.

   dmake now supports the MKS argument passing conventions.  The facility is
   enabled by setting .MKSARGS:=1 and is set by default in the startup.mk file
   if an MKS Korn shell is detected as being the active command interpretter.
