💾 Archived View for gmi.noulin.net › man › man3 › __setfpucw.3.gmi captured on 2022-06-12 at 06:48:08. Gemini links have been rewritten to link to archived content

View Raw

More Information

-=-=-=-=-=-=-

__SETFPUCW(3)                                                           Linux Programmer's Manual                                                          __SETFPUCW(3)

NAME
       __setfpucw - set FPU control word on i386 architecture (obsolete)

SYNOPSIS
       #include <i386/fpu_control.h>

       void __setfpucw(unsigned short control_word);

DESCRIPTION
       __setfpucw()  transfers  control_word to the registers of the FPU (floating-point unit) on the i386 architecture.  This was used to control floating-point preci‐
       sion, rounding and floating-point exceptions.

CONFORMING TO
       This function was a nonstandard GNU extension.

NOTES
       As of glibc 2.1 this function does not exist anymore.  There are new functions from C99, with prototypes  in  <fenv.h>,  to  control  FPU  rounding  modes,  like
       fegetround(3),  fesetround(3),  and  the  floating-point environment, like fegetenv(3), feholdexcept(3), fesetenv(3), feupdateenv(3), and FPU exception handling,
       like feclearexcept(3), fegetexceptflag(3), feraiseexcept(3), fesetexceptflag(3), and fetestexcept(3).

       If direct access to the FPU control word is still needed, the _FPU_GETCW and _FPU_SETCW macros from <fpu_control.h> can be used.

EXAMPLES
       __setfpucw(0x1372)

       Set FPU control word on the i386 architecture to
            - extended precision
            - rounding to nearest
            - exceptions on overflow, zero divide and NaN

SEE ALSO
       feclearexcept(3)

       <fpu_control.h>

Linux                                                                          2021-03-22                                                                  __SETFPUCW(3)