HP-UX Reference (11i v1 05/09) - 3 Library Functions A-M (vol 6)

f
feupdateenv(3M) feupdateenv(3M)
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.
RETURN VALUE
None.
ERRORS
No errors are defined.
EXAMPLE
Store the current floating-point environment in
holdenv, hide spurious underflow exceptions, and con-
tinue 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 */
SEE ALSO
fegetenv(3M), feholdexcept(3M), fesetenv(3M), fenv(5).
Section 3−−258 Hewlett-Packard Company − 1 − HP-UX 11i Version 1: September 2005