to the registers of the FPU (floating-point unit) on the i386 architecture.
This was used to control floating-point precision,
rounding and floating-point exceptions.
This function was a nonstandard GNU extension.
As of glibc 2.1 this function does not exist anymore.
There are new functions from C99, with prototypes in
to control FPU rounding modes, like
and the floating-point environment, like
and FPU exception handling, like
If direct access to the FPU control word is still needed, the
can be used.