HPlogo HP-UX Reference > F

fegetexceptflag(3M)

HP-UX 11i Version 2: December 2007 Update
» 

Technical documentation

 » Table of Contents

 » Index

spacerspacerspacer
spacer
spacer
  		 
 

NAME

fegetexceptflag() — get floating-point exception flags

SYNOPSIS

#include <fenv.h>

Itanium(R)-based System 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 Itanium-based systems, 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.

RETURN VALUE

Itanium-based System Only

This function always returns 0, indicating that a representation was successfully stored.

PA-RISC Only

None.

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);

SEE ALSO

feclearexcept(3M), fegettrapenable(3M), feraiseexcept(3M), fesetexceptflag(3M), fesettrapenable(3M), fetestexcept(3M), fenv(5).

STANDARDS CONFORMANCE

fegetexceptflag() : ISO/IEC C99 (including Annex F, "IEC 60559 floating-point arithmetic")



fegetenv
  		 


fegetflushtozero