1ISLESSGREATER(3P) POSIX Programmer's Manual ISLESSGREATER(3P)
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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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12 islessgreater — test if x is less than or greater than y
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15 #include <math.h>
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17 int islessgreater(real-floating x, real-floating y);
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20 The functionality described on this reference page is aligned with the
21 ISO C standard. Any conflict between the requirements described here
22 and the ISO C standard is unintentional. This volume of POSIX.1‐2017
23 defers to the ISO C standard.
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25 The islessgreater() macro shall determine whether its first argument is
26 less than or greater than its second argument. The islessgreater(x, y)
27 macro is similar to (x) < (y) || (x) > (y); however, islessgreater(x,
28 y) shall not raise the invalid floating-point exception when x and y
29 are unordered (nor shall it evaluate x and y twice).
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32 Upon successful completion, the islessgreater() macro shall return the
33 value of (x) < (y) || (x) > (y).
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35 If x or y is NaN, 0 shall be returned.
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38 No errors are defined.
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40 The following sections are informative.
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43 None.
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46 The relational and equality operators support the usual mathematical
47 relationships between numeric values. For any ordered pair of numeric
48 values, exactly one of the relationships (less, greater, and equal) is
49 true. Relational operators may raise the invalid floating-point excep‐
50 tion when argument values are NaNs. For a NaN and a numeric value, or
51 for two NaNs, just the unordered relationship is true. This macro is a
52 quiet (non-floating-point exception raising) version of a relational
53 operator. It facilitates writing efficient code that accounts for NaNs
54 without suffering the invalid floating-point exception. In the SYNOPSIS
55 section, real-floating indicates that the argument shall be an expres‐
56 sion of real-floating type.
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59 None.
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62 None.
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65 isgreater(), isgreaterequal(), isless(), islessequal(), isunordered()
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67 The Base Definitions volume of POSIX.1‐2017, <math.h>
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70 Portions of this text are reprinted and reproduced in electronic form
71 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
72 table Operating System Interface (POSIX), The Open Group Base Specifi‐
73 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
74 Electrical and Electronics Engineers, Inc and The Open Group. In the
75 event of any discrepancy between this version and the original IEEE and
76 The Open Group Standard, the original IEEE and The Open Group Standard
77 is the referee document. The original Standard can be obtained online
78 at http://www.opengroup.org/unix/online.html .
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80 Any typographical or formatting errors that appear in this page are
81 most likely to have been introduced during the conversion of the source
82 files to man page format. To report such errors, see https://www.ker‐
83 nel.org/doc/man-pages/reporting_bugs.html .
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87IEEE/The Open Group 2017 ISLESSGREATER(3P)