Q27325: Example Passing Near Numeric Variables between BASIC and C

Article: Q27325
Product(s): See article
Version(s): 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | B_BasicCom S_C S_QuickC | mspl13_basic
Last Modified: 6-NOV-1989

The two programs shown below demonstrate how numeric variables can be
passed from compiled BASIC to Microsoft C by near reference.

This information about inter-language calling applies to QuickBASIC
Versions 4.00, 4.00b, and 4.50 for MS-DOS and to Microsoft BASIC
Compiler Versions 6.00 and 6.00b for MS-DOS and MS OS/2.

For more information about passing other types of parameters between
BASIC and C, and a list of which BASIC and C versions are compatible
with each other, query in the Software/Data Library on the following
word:

   BAS2C

Code Example
------------

The following BASIC program is BNUMNEAR.BAS, which passes each of the
standard numeric types to a C subroutine:

DECLARE SUB NumericNear CDECL (a%,b&,c!,d#)
a% = 32767
b& = 32769
c! = 123.312
d# = 129381.333#
CLS
CALL NumericNear(a%, b&, c!, d#)
END

The following program is CNUMNEAR.C, which prints out the standard
numeric values passed from BASIC:

#include <stdio.h>
void NumericNear(a, b, c, d)
   int near *a;
   long near *b;
   float near *c;
   double near *d;
 {
    printf("INTEGER %d  \n", *a);
    printf("LONG    %ld \n", *b);
    printf("FLOAT   %f  \n", *c);
    printf("DOUBLE  %lf \n", *d);
 }

To demonstrate these programs from an .EXE program, compile and link
as follows:

     BC BNUMNEAR.BAS;

     CL /c /AM CNUMNEAR.C;      < for Microsoft C Optimizing Compiler >

           or

     QCL /c /AM CNUMNEAR.C;     < for Microsoft QuickC Compiler >

     LINK /NOE BNUMNEAR CNUMNEAR;

BNUMNEAR.EXE produces the following output:

     INTEGER  32767
     LONG     32769
     FLOAT    123.311996
     DOUBLE   129381.333000