1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
|
/* Copyright (C) 1997, 1999 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 <bits/fenv.h>
__BEGIN_DECLS
/* Floating-point exception handling. */
/* Clear the supported exceptions represented by EXCEPTS. */
extern void feclearexcept (int __excepts) __THROW;
/* Store implementation-defined representation of the exception flags
indicated by EXCEPTS in the object pointed to by FLAGP. */
extern void fegetexceptflag (fexcept_t *__flagp, int __excepts) __THROW;
/* Raise the supported exceptions represented by EXCEPTS. */
extern void feraiseexcept (int __excepts) __THROW;
/* Set complete status for exceptions indicated by EXCEPTS according to
the representation in the object pointed to by FLAGP. */
extern void fesetexceptflag (__const fexcept_t *__flagp, int __excepts) __THROW;
/* Determine which of subset of the exceptions specified by EXCEPTS are
currently set. */
extern int fetestexcept (int __excepts) __THROW;
/* Rounding control. */
/* Get current rounding direction. */
extern int fegetround (void) __THROW;
/* Establish the rounding direction represented by ROUND. */
extern int fesetround (int __rounding_direction) __THROW;
/* Floating-point environment. */
/* Store the current floating-point environment in the object pointed
to by ENVP. */
extern void fegetenv (fenv_t *__envp) __THROW;
/* 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 (fenv_t *__envp) __THROW;
/* Establish the floating-point environment represented by the object
pointed to by ENVP. */
extern void fesetenv (__const fenv_t *__envp) __THROW;
/* 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 (__const fenv_t *__envp) __THROW;
__END_DECLS
#endif /* fenv.h */
|
