fegetround(3p) — Справочная страница Linux

FEGETROUND(3P)          POSIX Programmer's Manual         FEGETROUND(3P)

ПРОЛОГ

       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.

ИМЯ

       fegetround, fesetround — get and set current rounding direction

СИНТАКСИС

       #include <fenv.h>

       int fegetround(void);
       int fesetround(int round);

ОПИСАНИЕ

       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.

       The fegetround() function shall get the current rounding
       direction.

       The fesetround() function shall establish the rounding direction
       represented by its argument round.  If the argument is not equal
       to the value of a rounding direction macro, the rounding
       direction is not changed.

ЗНАЧЕНИЕ, ВОЗВРАЩАЕМОЕ ФУНКЦИЕЙ

       The fegetround() function shall return the value of the rounding
       direction macro representing the current rounding direction or a
       negative value if there is no such rounding direction macro or
       the current rounding direction is not determinable.

       The fesetround() function shall return a zero value if and only
       if the requested rounding direction was established.

ОШИБКИ

       No errors are defined.

       The following sections are informative.

ПРИМЕРЫ

       The following example saves, sets, and restores the rounding
       direction, reporting an error and aborting if setting the
       rounding direction fails:

           #include <fenv.h>
           #include <assert.h>
           void f(int round_dir)
           {
               #pragma STDC FENV_ACCESS ON
               int save_round;
               int setround_ok;
               save_round = fegetround();
               setround_ok = fesetround(round_dir);
               assert(setround_ok == 0);
               /* ... */
               fesetround(save_round);
               /* ... */
           }

ИСПОЛЬЗОВАНИЕ В ПРИЛОЖЕНИЯХ

       None.

ОБЪЯСНЕНИЕ

       None.

НАПРАВЛЕНИЯ РАЗВИТИЯ

       None.

СМОТРИТЕ ТАКЖЕ

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

АВТОРСКИЕ ПРАВА

       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 at http://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, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group               2017                    FEGETROUND(3P)

Страницы, которые ссылаются на эту страницу: fenv.h(0p), fesetround(3p)