HP-UX Reference (11i v3 07/02) - 3 Library Functions A-M (vol 6)

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fegettrapenable(3M) fegettrapenable(3M)

NAME

fegettrapenable() - get ﬂoating-point exception trap enables

SYNOPSIS

#include <fenv.h>

int fegettrapenable(void);

DESCRIPTION

The fegettrapenable()

function determines which ﬂoating-point exception traps are currently

enabled.

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 HP 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 optimiza-

tions 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

The

fegettrapenable()

function returns the bitwise OR of the ﬂoating-point exception macros

corresponding to the currently enabled exception traps. The macros are

FE_INEXACT , FE_DIVBYZERO ,

FE_UNDERFLOW , FE_OVERFLOW , and FE_INVALID. FE_ALL_EXCEPT

represents all the ﬂoating-

point exceptions.

ERRORS

No errors are deﬁned.

EXAMPLES

Retrieve the current trap settings and determine whether a trap for the divide by zero exception is enabled.

#include <fenv.h>

/*...*/

if (fegettrapenable() & FE_DIVBYZERO)

printf("divide by zero trap set\\n");

AUTHOR

fegettrapenable() was developed by HP and is not required by any current standard.