Q57362: Variable Length String Passed from BASIC PDS 7.00 to C

Article: Q57362
Product(s): See article
Version(s): 7.00   | 7.00
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | SR# S891017-100 | mspl13_basic
Last Modified: 17-JAN-1990

The example below demonstrates how to pass a variable-length string
from a compiled BASIC program to a C program. This information applies
to Microsoft BASIC Professional Development System (PDS) 7.00 for
MS-DOS and MS OS/2.

BASIC to C Example
------------------

Compile and link as follows:

Compile:  BC /Fs/d Bastest.bas;
          QCL /AM Ctest.c /c

Link:     LINK /noe/nod Bastest+Ctest,,,BRT70EFR+MLIBCE;

REM ===== BASIC PROGRAM =====
DECLARE SUB StringFar CDECL (BYVAL p1o AS INTEGER, BYVAL p1s AS
INTEGER, SEG p3 AS INTEGER)
CLS
a$ = "This is a test" + CHR$(0)
CALL StringFar(SADD(a$), SSEG(a$), LEN(a$))
PRINT "Back from C"
END
/* C sub-program */
#include <e:\qc2\include\stdio.h>
void StringFar(a,len)
   char far *a;
    int *len;
 {
    int i;
    printf("The string is : %s \n\n",a);
    printf(" Index       Value       Character\n");
    for (i=0;i < *len; i++)
       {
         printf("  %2d          %3d
%c\n",i,a[i],a[i]);
       };
 }

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