__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 precision, 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, fesetround, and the floating-point environment, like fegetenv, feholdexcept,
       fesetenv, feupdateenv and FPU exception handling, like feclearexcept,  fegetexceptflag,  feraiseexcept,  fesetexceptflag,
       fetestexcept.

       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.

EXAMPLE
       __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>

COLOPHON
       This page is part of release 3.25 of the Linux man-pages project.  A description of the project,  and  information  about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



Linux                                                      1997-03-08                                              __SETFPUCW(3)