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fegetround(3p) — Linux manual page

FEGETROUND(3P)          POSIX Programmer's ManualFEGETROUND(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

       fegetround, fesetround — get and set current rounding direction

SYNOPSIS        top

       #include <fenv.h>       int fegetround(void);       int fesetround(intround);

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.       Thefegetround() function shall get the current rounding       direction.       Thefesetround() function shall establish the rounding direction       represented by its argumentround.  If the argument is not equal       to the value of a rounding direction macro, the rounding direction       is not changed.

RETURN VALUE        top

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

ERRORS        top

       No errors are defined.The following sections are informative.

EXAMPLES        top

       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);               /* ... */           }

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

       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                2017FEGETROUND(3P)

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

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