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NAME

       fegetround, fesetround - get and set current rounding direction

SYNOPSIS

       #include <fenv.h>

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

DESCRIPTION

       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.

RETURN VALUE

       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.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       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

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       The Base Definitions volume of IEEE Std 1003.1-2001, <fenv.h>

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 .