feraiseexcept (3p) - Linux Manuals

feraiseexcept: raise floating-point exception

PROLOG

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

feraiseexcept - raise floating-point exception

SYNOPSIS

#include <fenv.h>

int feraiseexcept(int excepts);

DESCRIPTION

The feraiseexcept() function shall attempt to raise the supported floating-point exceptions represented by the argument excepts. The order in which these floating-point exceptions are raised is unspecified. Whether the feraiseexcept() function additionally raises the inexact floating-point exception whenever it raises the overflow or underflow floating-point exception is implementation-defined.

RETURN VALUE

If the argument is zero or if all the specified exceptions were successfully raised, feraiseexcept() shall return zero. Otherwise, it shall return a non-zero value.

ERRORS

No errors are defined.

The following sections are informative.

EXAMPLES

None.

APPLICATION USAGE

The effect is intended to be similar to that of floating-point exceptions raised by arithmetic operations. Hence, enabled traps for floating-point exceptions raised by this function are taken.

RATIONALE

Raising overflow or underflow is allowed to also raise inexact because on some architectures the only practical way to raise an exception is to execute an instruction that has the exception as a side effect. The function is not restricted to accept only valid coincident expressions for atomic operations, so the function can be used to raise exceptions accrued over several operations.

FUTURE DIRECTIONS

None.

COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .