1FEGETROUND(3P)             POSIX Programmer's Manual            FEGETROUND(3P)
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PROLOG

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

12       fegetround, fesetround - get and set current rounding direction
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SYNOPSIS

15       #include <fenv.h>
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17       int fegetround(void);
18       int fesetround(int round);
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DESCRIPTION

22       The fegetround() function shall get the current rounding direction.
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24       The fesetround() function shall establish the rounding direction repre‐
25       sented by its argument round. If the argument is not equal to the value
26       of a rounding direction macro, the rounding direction is not changed.
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RETURN VALUE

29       The fegetround() function shall return the value of the rounding direc‐
30       tion  macro  representing  the current rounding direction or a negative
31       value if there is no such  rounding  direction  macro  or  the  current
32       rounding direction is not determinable.
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34       The  fesetround() function shall return a zero value if and only if the
35       requested rounding direction was established.
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ERRORS

38       No errors are defined.
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40       The following sections are informative.
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EXAMPLES

43       The following example saves, sets, and restores the rounding direction,
44       reporting  an  error  and  aborting  if  setting the rounding direction
45       fails:
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48              #include <fenv.h>
49              #include <assert.h>
50              void f(int round_dir)
51              {
52                  #pragma STDC FENV_ACCESS ON
53                  int save_round;
54                  int setround_ok;
55                  save_round = fegetround();
56                  setround_ok = fesetround(round_dir);
57                  assert(setround_ok == 0);
58                  /* ... */
59                  fesetround(save_round);
60                  /* ... */
61              }
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APPLICATION USAGE

64       None.
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RATIONALE

67       None.
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FUTURE DIRECTIONS

70       None.
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SEE ALSO

73       The Base Definitions volume of IEEE Std 1003.1-2001, <fenv.h>
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76       Portions of this text are reprinted and reproduced in  electronic  form
77       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
78       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
79       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
80       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
81       event of any discrepancy between this version and the original IEEE and
82       The Open Group Standard, the original IEEE and The Open Group  Standard
83       is  the  referee document. The original Standard can be obtained online
84       at http://www.opengroup.org/unix/online.html .
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88IEEE/The Open Group                  2003                       FEGETROUND(3P)
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