How to get the fraction part of a float as an integer?

I wonder how I can get the fraction part of a float number. For example, I want to get the integer 75 of the float 56.75. Something like,
frac(56.75) = 75

Thanks in advance.

Here's a rather hackish way....

Code:

int frac(double a)
{
   int b;
   b = floor(a);
   b = (a-b) * 100;
   return b;
}

That should work for numbers with 2 after the decimal point....