COPYSIGN(3P)

💖 COPYSIGN(3P) — POSIX Programmer's Manual 💖

okay bestie, welcome to the POSIX Programmer's Manual entry for copysign and its little float friends. pull up a chair, grab a boba, we're doing math.h today 🧋✨

🌸 PROLOG 🌸

so like, this manual page is part of the POSIX Programmer's Manual, right? but heads up, 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 alternatively?? the interface may literally not be implemented on Linux at all. it's giving "check before you commit" 💀

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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);

three flavors, one vibe. double, float, long double — pick your fighter 🫶

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👑 DESCRIPTION 👑

the functionality described on this reference page is aligned with the ISO C standard. and like, any conflict between the requirements described here and the ISO C standard is unintentional, fr fr. this volume of POSIX.1‐2017 defers to the ISO C standard. so ISO C is the main character here and POSIX is just hyping it up 💅

these functions shall produce a value with the magnitude of x and the sign of y. that's it. that's the whole job. take the size from one, the vibe (positive/negative) from the other. iconic behavior honestly 🌈

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. so no, -0.0 isn't gonna sneak up on you here, she's positive-coded in that specific case 🎀

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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. literally exactly what the description said. no plot twist, no cliffhanger, no surprise reveal 💖

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🙈 ERRORS 🙈

No errors are defined.

the following sections are informative. (translation: the lore continues but it's optional reading, bestie ✨)

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🍓 EXAMPLES 🍓

None.

not a single one. the examples section said "not me" and left 🧚

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🌸 APPLICATION USAGE 🌸

None.

nothing here either. it's giving minimalist 🎀

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💅 RATIONALE 💅

None.

no reasoning was given. we simply vibe 🦋

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⭐ FUTURE DIRECTIONS ⭐

None.

the future is undefined but in a chill way ✨

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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. like, they're the final boss, no cap 🫶

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, ty for reading, stan copysign 💅✨ this masterpiece was brought to you by IEEE/The Open Group, 2017, on the COPYSIGN(3P) page — periodt. 💖