Expert: Joseph Moore - 7/28/2009

Question
Dear Sir,
I have problem in array of structure. When data member of structure taken in float datatype. It cant initialize the float variable by scanf(). As it shows a runtime error that,
"scanf : floating point not linked. Abnormal program termination."
The program is,
#include<stdio.h>
#include<conio.h>
void main()
{
  struct book
  {
     int id;
     char name[25];
     float price;
  }a[3];
  int i;
  clrscr();
  for(i=0;i<3;i++)
  {
     printf("\n\n===================");
     printf("\n DATA %d",i+1);
     printf("\n===================");
     printf("\nEnter Book ID:");
     scanf("%d",&a[i].id);
     printf("Enter Book Name:");
     scanf("%s",a[i].name);
     printf("Enter the Price:");
     scanf("%f",&a[i].price);
  }
  for(i=0;i<3;i++)
  {
     printf("\n\n===================");
     printf("\n DATA %d",i+1);
     printf("\n===================");
     printf("\nBook ID: %d",a[i].id);
     printf("\nBook Name: %s",a[i].name);
     printf("\nPrice: %f",a[i].price);
  }
  getch();
}
Plz help me for this problem.

With Regards,
Praful S

Answer
It sounds like you're using an old compiler that tries to leave out floating point operations if they aren't used (and doesn't properly detect when they're used sometimes) such as Borland TurboC.  The work-around for this is to include some function that clues the compiler in to the fact that you are using floating points.  You can call a built-in function (such as sqrtf) or you can add a dummy function (which you don't even have to call) such as:

void dummy(float*f){float v=*f; dummy(&v);}

Hope that helps!