NAME
feupdateenv() — update floating-point environment
SYNOPSIS
#include <fenv.h>
void feupdateenv(const fenv_t *envp);
DESCRIPTION
The
feupdateenv()
function saves the current exceptions in its automatic storage,
installs the floating-point environment represented through
envp,
and then raises the saved exceptions.
The argument
envp
must point to an object set by a call to
fegetenv()
or
feholdexcept(),
or equal the macro
FE_DFL_ENV.
The ISO/ANSI C committee has approved the
feupdateenv()
function for inclusion in the C9X draft standard.
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>.
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.
ERRORS
No errors are defined.
EXAMPLE
Store the current floating-point environment in
holdenv,
hide spurious underflow exceptions, and continue on any exceptions
that occur until the call to
feupdateenv()
is encountered.
#include <fenv.h>
/*...*/
fenv_t holdenv;
feholdexcept(&holdenv);
/* perform operations */
if (/* test for spurious underflow */)
feclearexcept(FE_UNDERFLOW);
feupdateenv(&holdenv); /* raise accumulated exceptions */
