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



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

SYNOPSIS
       #include <&lt;i386/fpu_control.h>&gt;

       void __setfpucw(unsigned short control_word);

DESCRIPTION
       __setfpucw() transfers control_word to the registers of the FPU (float-
       ing-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 non-standard GNU extension.

NOTES
       As  of  glibc  2.1 this function does not exist anymore.  There are new
       functions from C99, with prototypes in &lt;fenv.h&gt;, to control FPU  round-
       ing modes, like fegetround, fesetround, and the floating-point environ-
       ment, like fegetenv, feholdexcept, fesetenv, feupdateenv and FPU excep-
       tion handling, like feclearexcept, fegetexceptflag, feraiseexcept, fes-
       etexceptflag, fetestexcept.

       If direct  access  to  the  FPU  control  word  is  still  needed,  the
       _FPU_GETCW and _FPU_SETCW macros from &lt;fpu_control.h&gt; 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)
       &lt;fpu_control.h&gt;

COLOPHON
       This  page  is  part of release 3.05 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)