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feraiseexcept(3p) — Linux manual page

FERAISEEXCEPT(3P)       POSIX Programmer's ManualFERAISEEXCEPT(3P)

PROLOG        top

       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        top

       feraiseexcept — raise floating-point exception

SYNOPSIS        top

       #include <fenv.h>       int feraiseexcept(intexcepts);

DESCRIPTION        top

       The functionality described on this reference page is aligned with       the ISO C standard. Any conflict between the requirements       described here and the ISO C standard is unintentional. This       volume of POSIX.1‐2017 defers to the ISO C standard.       Theferaiseexcept() function shall attempt to raise the supported       floating-point exceptions represented by theexcepts argument. The       order in which these floating-point exceptions are raised is       unspecified, except that if theexcepts argument represents IEC       60559 valid coincident floating-point exceptions for atomic       operations (namely overflow and inexact, or underflow and       inexact), then overflow or underflow shall be raised before       inexact.  Whether theferaiseexcept() function additionally raises       the inexact floating-point exception whenever it raises the       overflow or underflow floating-point exception is implementation-       defined.

RETURN VALUE        top

       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        top

       No errors are defined.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       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        top

       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        top

       None.

SEE ALSO        top

feclearexcept(3p),fegetexceptflag(3p),fetestexcept(3p)       The Base Definitions volume of POSIX.1‐2017,fenv.h(0p)

COPYRIGHT        top

       Portions of this text are reprinted and reproduced in electronic       form from IEEE Std 1003.1-2017, Standard for Information       Technology -- Portable Operating System Interface (POSIX), The       Open Group Base Specifications Issue 7, 2018 Edition, Copyright       (C) 2018 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 athttp://www.opengroup.org/unix/online.html .       Any typographical or formatting errors that appear in this page       are most likely to have been introduced during the conversion of       the source files to man page format. To report such errors, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017FERAISEEXCEPT(3P)

Pages that refer to this page:fenv.h(0p), feclearexcept(3p), fegetexceptflag(3p), fetestexcept(3p)

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