COPYSIGN(3POSIX)

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

okay so this is copysign(3POSIX), and it lives in the POSIX Programmer's Manual 🎀

🌸 PROLOG 🌸

Heads up, bestie, this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ — so if you're on Linux, go consult the corresponding Linux manual page for the deets on Linux behavior. Or, plot twist, the interface might not even be implemented on Linux at all. 🙈

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✨ NAME ✨

copysign, copysignf, copysignl — number manipulation function 💅

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🦋 SYNOPSIS 🦋

#include <math.h>

double copysign(double x, double y);
float copysignf(float x, float y);
long double copysignl(long double x, long double y);

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💜 DESCRIPTION 💜

So 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? Unintentional, fr fr. This volume of POSIX.1‐2017 defers to the ISO C standard, periodt.

These functions shall produce a value with the magnitude of x and the sign of y. 🫶

And here's the little chaos corner: on implementations that represent a signed zero but do not treat negative zero consistently in arithmetic operations, these functions regard the sign of zero as positive. Noted. 👑

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🔥 RETURN VALUE 🔥

Upon successful completion, these functions shall return a value with the magnitude of x and the sign of y. That's it, that's the whole vibe check. ⭐

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💀 ERRORS 💀

No errors are defined. Iconic behavior, honestly.

The following sections are informative.

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🍓 EXAMPLES 🍓

None. 😭 (we stay unbothered)

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🌈 APPLICATION USAGE 🌈

None. ✨

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🧚 RATIONALE 🧚

None. 💜

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⭐ FUTURE DIRECTIONS ⭐

None. 🎀

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👑 SEE ALSO 👑

• signbit()
• 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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no cap, if something here looks busted, it's probably a conversion glitch — not the actual spec. the spec is always the main character. 💖

and that's the whole page, bestie!! brought to you by IEEE/The Open Group, dated 2017, under the manual name COPYSIGN(3POSIX) 🦋 mwah, go read the Linux page too, ily 💜✨