Readme file for using Watcom C/C++32 compiler version 9.5 to build 
user DLLs for Mathcad

To build a sample: (samples are under SOURCES subdirectory of 
your compiler directory)
Each sample has a compile.bat and a link.bat file associated with it.  
To build a sample project just call these files in sequence.


When using Watcom for the first time you should keep in mind the 
following points:
  a) The compiler crashes if EMM386 memory manager is installed.  
So take it out of your config.sys or autoexec.bat file if you have it.
  b) Make sure your include path includes 
watcom\h\nt;watcom\h;mstools\h where mstools\h contains the include 
files from Microsoft's WIN32 SDK (Watcom does not provide the 
Microsoft files).
  c) You have to compile using stack based argument passing 
conventions.  This is done by using the compiler directive /3s or /4s 
depending on whether you have a 386 or 486 processor.
  d) Running Watcom under DOS you need to set the path 
environment variable so that it includes watcom\bin;watcom\binb.  
Running under NT you have to set the user environment variables so 
that  the path includes watcom\binnt;watcom\binb. 
  e) DLL entry point function has to be called LibMain.
  f) Default structure alignment is 1 byte.  You have to set it to 8 by the 
directive /zp8.
  g) We have not provided an import library for MCADUSER.DLL 
because we had problems generating NT import libraries using the 
Watcom librarian WLINK.  Therefore, the functions in 
MCADUSER.DLL are demand-loaded.  Because of this the include 
file and the sources for Watcom are significantly different from the 
others.
  h) For more information see the sample source files and the 
readme.txt file in USEREFI subdirectory.


TYPICAL COMMAND LINES:

A typical compile line command for Watcom is:
  wcc386 /bd /3s /bt=nt /zp8 /i=c:\winmcad\userefi\watcom\include 
filename.c

 or, in relative notation for the samples,
  wcc386 /bd /3s /bt=nt /zp8 /i=..\..\include filename.c
 
/bd is for building a DLL; /3s so it uses stack based calling 
convention using 386 instructions; /bt=nt indicates we are building a 
32 bit DLL; /zp8 causes 8 byte alignment of non-character members 
within structures; /i= indicates the path where the include files might 
be (in this case path for MCADINCL.H for Watcom) and filename is 
the name of the file being compiled.
 
A typical link line command for Watcom is:
  wlink system nt_dll initinstance terminstance file {file1.obj file2.obj} 
name c:\winmcad\userefi\DLLname.dll

 or, in relative notation for the samples,
  wlink system nt_dll initinstance terminstance file {file1.obj file2.obj} 
name ..\..\..\DLLname.dll

system nt_dll indicates we are building a 32 bit DLL; initinstance and 
terminstance are needed if you link with any runtime libraries; file1 
and file2 are the names of the object files to be linked; DLLname is the 
name of the DLL to be built (this is optional and if not present it will 
use the name of the first object file for DLLname)