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write_rnd(3)
NAME
  write_rnd, read_rnd - sets and returns IEEE dynamic rounding mode for
  floating-point operations

SYNOPSIS
  #include <float.h>

  unsigned int write_rnd(
	  unsigned int rnd );

  unsigned int read_rnd(
	  void );

LIBRARY
  Standard C Library (libc.so, libc.a)

DESCRIPTION
  The write_rnd() function sets the dynamic rounding mode in the floating-
  point control register (fpcr) for IEEE floating-point operations and
  returns the previous dynamic rounding mode. Dynamic rounding mode for IEEE
  floating-point operations is enabled for code generated by the C compiler
  by specifying -fprm d to cc(1), and by using the d floating-point
  instruction operator in assembly language code.

  Specify rnd as one of the following constants defined in float.h:

  ________________________________________________
  Constant    Meaning
  ________________________________________________

  FP_RND_RZ   Round toward zero (chopped rounding)
  FP_RND_RN

	      Round toward nearest (normal
	      rounding)
  FP_RND_RP   Round toward plus infinity
  FP_RND_RM   Round toward minus infinity
  ________________________________________________

  The read_rnd() function returns the current dynamic rounding mode for
  floating-point operations.

RETURN VALUES
  The write_rnd() function returns the previous IEEE floating-point rounding
  mode. The read_rnd() function returns the current IEEE floating-point
  rounding mode.

SEE ALSO
  Commands: cc(1)

  Files: float.h

  Assembly Language Programmer's Guide

  Alpha Architecture Reference Manual

  IEEE Standard for Binary Floating-Point Arithmetic

Index for Section 3

Alphabetical listing for W

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