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 Example of Passing Fixed-Length Strings from C to Basic - Q47348
 
 To pass a string from Microsoft C to compiled Basic, the string must
 originate in Basic. A fixed-length string works best for this purpose.
 In the C module, you can modify the string, and Basic will recognize
 this modification because Basic is referencing the address of the
 string.
 
 More Information:
 
 The following program is an example of passing a fixed-length string
 from C to Basic (where the string is first allocated in Basic). Please
 note that the C module needs to use the medium memory model.
 
 Code Example
 ------------
 
 Compile Steps
 -------------
 
    BC callc.bas /o;
 
    cl /c /AM stringf.c
 
 Link Step
 ---------
 
    LINK callc+stringf /nod /noe ,,,vbdcl10e+mlibce;
 
 Basic Program
 -------------
 
 'CALLC.BAS
 DECLARE SUB StringFar CDECL (_
             BYVAL p1o AS INTEGER,_
             BYVAL p1s AS INTEGER,_
             p3 AS INTEGER)
 
 DIM array AS STRING * 15
 
 CLS
 array = "This is a test" + CHR$(0)
 CALL StringFar(VARPTR(array), VARSEG(array), LEN(array))
 LOCATE 20,20
 PRINT array
 END
 
 C Program
 ---------
 
 /* stringf.c */
 
 #include <stdio.h>
 
 void StringFar(char far *a, int *len) {
    int i;
 
    printf("The string is : %Fs\\",a);
    printf(" Index       Value       Character\");
 
    for (i = 0;i < *len; i++) {
       printf("  %2d       %3d      %c\", i, a[i], a[i]);
    }
 
 /* This loop writes over the end of the string */
    for (i = 10; i < *len; i++) {
       a[i] = 64;    // ASCII value for '@'
    }
 }
 
 Output
 ------
 
 The string is : This is a test
 
 Index       Value       Character
  0           84          T
  1          104          h
  2          105          i
  3          115          s
  4           32
  5          105          i
  6          115          s
  7           32
  8                       a
  9           32
 10          116          t
 11          101          e
 12          115          s
 13          116          t
 
                     This is a @@@@