_fsqrt -- Calculate Square Root

Format

#include <builtin.h>
double _fsqrt(double x);

Language Level: Extension
_fsqrt computes the square root of x using the FSQRT 80387 instruction. Note that this function does not set errno as the sqrt function does. If you pass a negative value to this function, an exception is generated.

Note: _fsqrt is a built-in function, which means it is implemented as an inline instruction and has no backing code in the library. For this reason:

Return Value
_fsqrt returns the value of the square root of x.

Example
This example calculates the square root of 4.

#include <builtin.h>
#include <stdio.h>
int main(void)
{
   double x;
   x = 4.0;
   printf("The square root of %lf is %lf.\n", x, _fsqrt(x));
   return 0;
   /********************************************************
      The output should be:
      The square root of 4.000000 is 2.000000.
   ********************************************************/
}



sqrt -- Calculate Square Root
<math.h>