NAME

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

LIBRARY

       Standard C library (libc, -lc)

SYNOPSIS

       #include <i386/fpu_control.h>

       [[deprecated]] 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.

STANDARDS

       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>