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/* Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/*
* ISO C 9X 7.6: Floating-point environment <fenv.h>
*/
#ifndef _FENV_H
#define _FENV_H 1
#include <features.h>
/* Get the architecture dependend definitions. The following definitions
are expected to be done:
fenv_t type for object representing an entire floating-point
environment
FE_DFL_ENV macro of type pointer to fenv_t to be used as the argument
to functions taking an argument of type fenv_t; in this
case the default environment will be used
fexcept_t type for object representing the floating-point exception
flags including status associated with the flags
The following macros are defined iff the implementation supports this
kind of exception.
FE_INEXACT inexact result
FE_DIVBYZERO devision by zero
FE_UNDERFLOW result not representable due to underflow
FE_OVERFLOW result not representable due to overflow
FE_INVALID invalid operation
FE_ALL_EXCEPT bitwise OR of all supported exceptions
The next macros are defined iff the appropriate rounding mode is
supported by the implementation.
FE_TONEAREST round to nearest
FE_UPWARD round toward +Inf
FE_DOWNWARD round toward -Inf
FE_TOWARDZERO round toward 0
*/
#include <fenvbits.h>
__BEGIN_DECLS
/* Floating-point exception handling. */
/* Clear the supported exceptions represented by EXCEPTS. */
extern void feclearexcept __P ((int __excepts));
/* Store implementation-defined representation of the exception flags
indicated by EXCEPTS in the object pointed to by FLAGP. */
extern void fegetexceptflag __P ((fexcept_t *__flagp, int __excepts));
/* Raise the supported exceptions represented by EXCEPTS. */
extern void feraiseexcept __P ((int __excepts));
/* Set complete status for exceptions inidicated by EXCEPTS according to
the representation in the object pointed to by FLAGP. */
extern void fesetexceptflag __P ((__const fexcept_t *__flagp, int __excepts));
/* Determine which of subset of the exceptions specified by EXCEPTS are
currently set. */
extern int fetestexcept __P ((int __excepts));
/* Rounding control. */
/* Get current rounding direction. */
extern int fegetround __P ((void));
/* Establish the rounding direction represented by ROUND. */
extern int fesetround __P ((int __rounding_direction));
/* Floating-point environment. */
/* Store the current floating-point environment in the object pointed
to by ENVP. */
extern void fegetenv __P ((fenv_t *__envp));
/* Save the current environment in the object pointed to by ENVP, clear
exception flags and install a non-stop mode (if available) for all
exceptions. */
extern int feholdexcept __P ((fenv_t *__envp));
/* Establish the floating-point environment represented by the object
pointed to by ENVP. */
extern void fesetenv __P ((__const fenv_t *__envp));
/* Save current exceptions in temporary storage, install environment
represented by object pointed to by ENVP and raise exceptions
according to saved exceptions. */
extern void feupdateenv __P ((__const fenv_t *__envp));
__END_DECLS
#endif /* fenv.h */
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