title: Why and when should one call _fpreset( )?
body: <p>The only documentation I can find (on MSDN or otherwise) is that a call to <code>_fpreset()</code> "resets the floating-point package."  What is the "floating point package?"  Does this also clear the FPU status word?  I see documentation that says to call <code>_fpreset()</code> when recovering from a SIGFPE, but doesn't <code>_clearfp()</code> do this as well?  Do I need to call both?</p>
  
  <p>I am working on an application that unmasks some FP exceptions (using <code>_controlfp()</code>).  When I want to reset the FPU to the default state (say, when calling to .NET code), should I just call <code>_clearfp()</code>, <code>_fpreset()</code>, or <em>both</em>.  This is performance critical code, so I don't want to call both if I don't have to...</p>