1ISLESSEQUAL(3P)            POSIX Programmer's Manual           ISLESSEQUAL(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

13       islessequal — test if x is less than or equal to y
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SYNOPSIS

16       #include <math.h>
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18       int islessequal(real-floating x, real-floating y);
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DESCRIPTION

21       The functionality described on this reference page is aligned with  the
22       ISO C  standard.  Any  conflict between the requirements described here
23       and the ISO C standard is unintentional. This  volume  of  POSIX.1‐2008
24       defers to the ISO C standard.
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26       The  islessequal()  macro shall determine whether its first argument is
27       less than or equal to its second argument. The value of  islessequal(x,
28       y)  shall  be equal to (x) <= (y); however, unlike (x) <= (y), islesse‐
29       qual(x, y) shall not raise the invalid floating-point exception when  x
30       and y are unordered.
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RETURN VALUE

33       Upon  successful  completion,  the islessequal() macro shall return the
34       value of (x) <= (y).
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36       If x or y is NaN, 0 shall be returned.
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ERRORS

39       No errors are defined.
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41       The following sections are informative.
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EXAMPLES

44       None.
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APPLICATION USAGE

47       The relational and equality operators support  the  usual  mathematical
48       relationships  between  numeric values. For any ordered pair of numeric
49       values, exactly one of the relationships (less, greater, and equal)  is
50       true.  Relational operators may raise the invalid floating-point excep‐
51       tion when argument values are NaNs. For a NaN and a numeric  value,  or
52       for  two NaNs, just the unordered relationship is true. This macro is a
53       quiet (non-floating-point exception raising) version  of  a  relational
54       operator.  It facilitates writing efficient code that accounts for NaNs
55       without suffering the invalid floating-point exception. In the SYNOPSIS
56       section,  real-floating indicates that the argument shall be an expres‐
57       sion of real-floating type.
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RATIONALE

60       None.
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FUTURE DIRECTIONS

63       None.
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SEE ALSO

66       isgreater(), isgreaterequal(), isless(), islessgreater(), isunordered()
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68       The Base Definitions volume of POSIX.1‐2008, <math.h>
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71       Portions of this text are reprinted and reproduced in  electronic  form
72       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
73       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
74       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
75       cal and Electronics Engineers,  Inc  and  The  Open  Group.   (This  is
76       POSIX.1-2008  with  the  2013  Technical Corrigendum 1 applied.) In the
77       event of any discrepancy between this version and the original IEEE and
78       The  Open Group Standard, the original IEEE and The Open Group Standard
79       is the referee document. The original Standard can be  obtained  online
80       at http://www.unix.org/online.html .
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82       Any  typographical  or  formatting  errors that appear in this page are
83       most likely to have been introduced during the conversion of the source
84       files  to  man page format. To report such errors, see https://www.ker
85       nel.org/doc/man-pages/reporting_bugs.html .
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89IEEE/The Open Group                  2013                      ISLESSEQUAL(3P)
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