NAME
fegetexceptflag() — get floating-point exception flags
SYNOPSIS
#include <fenv.h>
HP Integrity Server Only
int fegetexceptflag(fexcept_t *flagp, int excepts);
PA-RISC Only
void fegetexceptflag(fexcept_t *flagp, int excepts);
DESCRIPTION
The
fegetexceptflag()
function stores a representation of the states of the floating-point
exception flags indicated by the argument
excepts
in the object pointed to by the argument
flagp.
The
excepts
argument can be constructed as a bitwise OR of the floating-point
exception macros:
FE_INEXACT,
FE_DIVBYZERO,
FE_UNDERFLOW,
FE_OVERFLOW,
and
FE_INVALID.
FE_ALL_EXCEPT
represents all the floating-point exceptions.
The object into which the floating-point exception flags are stored
can be passed to
fesetexceptflag
to restore the system exception flags, but the representation of the
floating-point exception flags stored in the object is otherwise
unspecified.
Use
fetestexcept(),
instead of
fegetexceptflag(),
to determine which floating-point exception flags are set.
USAGE
To use this function, compile either with the default
-Ae
option or with the
-Aa
and
-D_HPUX_SOURCE
options. Make sure your program includes
<fenv.h>.
For Integrity servers, specify
+Ofenvaccess
on the compiler command line or
place the call to this function under the effect of
an affirmative
FENV_ACCESS
pragma:
#pragma STDC FENV_ACCESS ON
If the
FENV_ACCESS
pragma is placed outside of any top-level
declarations in a file, the pragma will apply to all declarations in
the compilation following the pragma until another
FENV_ACCESS
pragma
is encountered or until the end of the file is reached.
If the
FENV_ACCESS
pragma is placed at the beginning of a block
(compound statement), the pragma will apply until another
FENV_ACCESS
pragma is encountered or until the end of the block is reached.
For PA-RISC, you might need to use the
+Onomoveflops
compiler option
in order to prevent optimizations that can undermine the specified behavior
of this function.
Link in the math library by specifying
-lm
on the compiler or linker command line.
For more information, see the
HP-UX floating-point guide for HP Integrity servers
at the following site:
http://www.hp.com/go/fp.
RETURN VALUE
Integrity Server Only
This function always returns 0, indicating that a representation was
successfully stored.
ERRORS
No errors are defined.
EXAMPLES
Store the overflow and invalid floating-point exception flags:
#include <fenv.h>
/*...*/
fexcept_t flags;
/*...*/
fegetexceptflag(&flags, FE_OVERFLOW | FE_INVALID);
STANDARDS CONFORMANCE
fegetexceptflag()
: ISO/IEC C99 (including Annex F, "IEC 60559 floating-point arithmetic")
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