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' This example uses the VARPTR and VARSEG functions in a CALL statement
' to pass a Basic array to a C function.
 
' Note: To run this example, you must separately compile the C function
' with the large-model (/AL) switch and either place the object module in
' a Quick library or link it to the Basic program.
 
' To try this example:
' 1. Choose New Project from the File menu
' 2. Copy the code example below to the code window
' 3. Press F5 to run the example
 
 DEFINT A-Z
 DECLARE SUB AddArr CDECL (BYVAL Offs, BYVAL Segm, BYVAL Num)
 DIM A(1 TO 100) AS INTEGER
 
 CLS                          ' Clear the screen
 FOR I = 1 TO 15              ' Fill the array with the numbers 1 to 15
     A(I) = I
 NEXT I
 
' Call the C function. AddArr expects a far address (segment and offset).
' Because CDECL puts things on the stack from right to left, place the
' offset VARPTR(A(1)) first in the list, followed by the segment
' VARSEG(A(1)).
 
 CALL AddArr(VARPTR(A(1)), VARSEG(A(1)), 15)
 FOR I = 1 TO 15              ' Print the modified array
     PRINT A(I)
 NEXT I
 END
 
' /* C Function AddArr */
' /* Add one to the first num elements of array arr.*/
' void far addarr(arr,num)
' int far *arr;
' int num;
' {
'     int i;
'     for(i=0;i<num;i++) arr[i]++;
' }