ISLESS(3P)

👑 ISLESS(3P) — POSIX Programmer's Manual, bestie edition 💅

okay so this is ISLESS(3P), straight out of the POSIX Programmer's Manual. it's giving math.h energy and honestly? it's iconic. let's get into it ✨

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🌸 PROLOG 🌸

Real talk before we start: this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (so like, go check the corresponding Linux manual page for details on how Linux actually behaves, no cap), or the interface may not even be implemented on Linux at all. 💀

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✨ NAME ✨

isless — test if x is less than y 🫶

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🎀 SYNOPSIS 🎀

#include <math.h>

int isless(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. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1‐2017 defers to the ISO C standard. periodt. 💅

The isless() macro shall determine whether its first argument is less than its second argument. The value of isless(x, y) shall be equal to (x) < (y); however — and this is the plot twist, bestie — unlike (x) < (y), isless(x, y) shall not raise the invalid floating-point exception when x and y are unordered. 😌

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🔥 RETURN VALUE 🔥

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

If x or y is NaN, 0 shall be returned. (yes, zero. NaN said "not today" 🙈)

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💀 ERRORS 💀

No errors are defined.

The following sections are informative. (translation: they're the vibes section, not the rules section 🧚)

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🌈 EXAMPLES 🌈

None. (we're literally just that self-explanatory ✨)

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

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⭐ RATIONALE ⭐

None. (no thoughts, just vibes 🎀)

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💜 FUTURE DIRECTIONS 💜

None. (she's perfect, she's staying exactly how she is 💅)

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🌟 SEE ALSO 🌟

• isgreater()
• isgreaterequal()
• islessequal()
• islessgreater()
• isunordered()

The Base Definitions volume of POSIX.1‐2017, <math.h> — the whole squad is here, fr fr 🫶

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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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lowkey important bestie: if this page and the official IEEE / The Open Group Standard ever disagree, the original standard wins. this one's just the group chat recap, not the receipt. 🫶

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and that's the whole page!! mwah 💋 this was brought to you by IEEE/The Open Group, dated 2017, and yes the page itself is literally named ISLESS(3P). slay, stay NaN-aware, and go be the quiet non-exception-raising main character you were born to be 💖✨🎀🦋🌸💅🫶👑🌈⭐