ISLESSEQUAL(3P)

💖 ISLESSEQUAL(3P) — the POSIX Programmer's Manual, bestie edition 💖

okay so real talk, this page lives in the POSIX Programmer's Manual and it's all about that islessequal life. Let's get into it. 🦋

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🌸 PROLOG 🌸

This manual page is part of the POSIX Programmer's Manual. Heads up tho: the Linux implementation of this interface may differ — so if you're on Linux, pls go consult the corresponding Linux manual page for the deets on Linux behavior. Or, alternatively, the interface may just not be implemented on Linux at all. 🙈 Either way, iykyk.

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✨ NAME ✨

islessequal — test if x is less than or equal to y. that's it, that's the whole job, and she does it flawlessly 💅

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🎀 SYNOPSIS 🎀

#include <math.h>

int islessequal(real-floating x, real-floating y);

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👑 DESCRIPTION 👑

The functionality described on this reference page is aligned with the ISO C standard. And like, if there's any conflict between the requirements described here and the ISO C standard? That conflict is unintentional, no cap. This volume of POSIX.1‐2017 defers to the ISO C standard. the ISO C standard is the main character here, we're just supporting cast. 🫶

The islessequal() macro shall determine whether its first argument is less than or equal to its second argument. The value of islessequal(x, y) shall be equal to (x) <= (y). BUT — and this is the iconic part — unlike (x) <= (y), islessequal(x, y) shall not raise the invalid floating-point exception when x and y are unordered. she's quiet, she's polite, she doesn't cause a scene. 🌸

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🌈 RETURN VALUE 🌈

Upon successful completion, the islessequal() macro shall return the value of (x) <= (y).

If x or y is NaN, 0 shall be returned. (not me being like "wait, NaN isn't less than or equal to anything" — correct, bestie, that's literally why it returns 0. 💀)

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⭐ ERRORS ⭐

No errors are defined. zero. none. she simply does not have an error era.

The following sections are informative. 📝

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🍓 EXAMPLES 🍓

None. we're keeping it mysterious. ✨

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🧚 APPLICATION USAGE 🧚

The relational and equality operators support the usual mathematical relationships between numeric values. For any ordered pair of numeric values, exactly one of the relationships (less, greater, and equal) is true.

Relational operators may raise the invalid floating-point exception when argument values are NaNs. For a NaN and a numeric value, or for two NaNs, just the unordered relationship is true.

This macro is a quiet (non-floating-point exception raising) version of a relational operator. It facilitates writing efficient code that accounts for NaNs without suffering the invalid floating-point exception. Like… she's the chill version of <=. lowkey the bestie who doesn't start drama at the function party. 💅

In the SYNOPSIS section, real-floating indicates that the argument shall be an expression of real-floating type.

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💜 RATIONALE 💜

None. moving on, we're not gonna dwell. 🙈

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🦋 FUTURE DIRECTIONS 🦋

None. the future is bright and also empty. ✨

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🔥 SEE ALSO 🔥

• isgreater()
• isgreaterequal()
• isless()
• islessgreater()
• isunordered()

The Base Definitions volume of POSIX.1‐2017, <math.h>

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📜 COPYRIGHT 📜

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 at http://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, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

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and that's the whole page, bestie 💖 written by IEEE/The Open Group, 2017 — yes, the IEEE/The Open Group really did that, 2017 era, and honestly? iconic. periodt. 💅✨