bionic (3) __setfpucw.3.gz

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(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.

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

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