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   4. C RTL (Run Time Library) functions
   -------------------------------------
     One last point that may be obvious to some of you is that any external C
     functions you call from PowerBASIC can *NOT* use any of the C run-time
     library functions (i.e.  printf, itoa, etc.).  The reason for that being
     that the C run-time library is not available.
------------------------------------------------------------------------------
-
    Let's look at a concrete (if somewhat simplistic) example.  The following
    C function takes an integer, adds it to itself and returns the result to
    your PowerBASIC program.
    C source.
    ---------
    
/------------------------------------------------------------------------
    // File: times2.c
    // Desc: Example of a C function to be linked with PowerBASIC code
    //
    // Compile with: BCC -c -ml -zCcode -zRdata times2.c
    //
    // The above switches do the following:
    //   -c      = Compile (only, don't link) to .OBJ file
    //   -ml     = Use LARGE memory model (required for PowerBASIC)
    //   -zCcode = Name of code segment is CODE
    //   -zRdata = Name of data segment is DATA
    //
    // The int pascal below tells BCC (or BC) to use PASCAL parameter passing
    // conventions (also used by PowerBASIC).
    
------------------------------------------------------------------------
    int pascal times2(int x)
    {
      int y;
      y = x + x;
      return y;
    }
    PowerBASIC source.
    ------------------
    
=========================================================================
    ' File: ctest.bas
    ' Desc: Example of using a C routine with PowerBASIC
    
========================================================================
    $CPU      8086          ' Works on all PCs
    $DIM      ALL           ' All variables must be declared before using 
hem
    $LIB      ALL OFF       ' No additional libraries are needed
    $ERROR    ALL OFF       ' Turn off all of PowerBASI's error checking
    $COMPILE  EXE           ' Generate an EXEcutable file
    $OPTIMIZE SPEED         ' Optimize for faster code
    DECLARE FUNCTION Times2(BYVAL INTEGER) AS INTEGER
    $LINK   "times2.obj"
    DIM MyVar AS INTEGER
    MyVar = 4                               ' Assign an initial value to 
yVar
    PRINT "MyVar's initial value: "; MyVar  ' Show that value
    MyVar = Times2(MyVar)                   ' Call C routine to process it
    PRINT "MyVar after Times2:    "; MyVar  ' Show new value
    When you run this program, the first PRINT statement will show 4 which
    is the value assigned to MyVar.  The second PRINT statement will show
    8 which is the value returned by the C function ""times2".
==============================================================================
=
                   Part II: Using Microsoft C, C++, etc...
==============================================================================
=
  Most of what was said above concerning Borland C, C++ also applies to
  Microsoft C, C++ with a few exceptions.
  The following notes only apply to the command line version of the Microsoft
  compiler.  The Microsoft command line compiler is CL.EXE.  This is a
  protected mode program requiring a DPMI server to be available.
  1. Parameter passing conventions
  --------------------------------
    See Part I section 1, above.
  2. Memory model
  ---------------
    The "C" code must be compiled using the LARGE memory model (because
    PowerBASIC uses FAR (32-bit) pointers exclusively.  This produces
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