ISINF(3POSIX)

📦 version 2017a, in debian bookworm, debian trixie, ubuntu jammy, ubuntu noble, ubuntu resolute, ubuntu stonking

💖 ISINF(3POSIX) 💖

okay bestie, so you found yourself in the POSIX Programmer's Manual — iconic. this is isinf, from the POSIX Programmer's Manual, and she's here to answer one (1) very important question: is this number literally infinity? ✨

🌸 PROLOG 🌸

ok so 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 the details of Linux behavior, fr), or honestly the interface might not even be implemented on Linux at all. 💀 no cap.

✨ NAME ✨

isinf — test for infinity 🦋

🎀 SYNOPSIS 🎀

#include <math.h>

int isinf(real-floating x);

👑 DESCRIPTION 👑

bestie, listen. 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 — nobody's trying to start drama. this volume of POSIX.1‐2017 defers to the ISO C standard. periodt. 💅

the isinf() macro shall determine whether its argument value is an infinity (positive or negative, she doesn't discriminate, we love an inclusive queen). 🫶

first things first: an argument represented in a format wider than its semantic type is converted to its semantic type. only then does the determination happen, and it's based on the type of the argument. so like, vibe check first, judgment second. 🌈

🔥 RETURN VALUE 🔥

the isinf() macro shall return a non-zero value if and only if its argument has an infinite value. that's it, that's the whole personality. ⭐

💜 ERRORS 💜

no errors are defined. literally none. she's unbothered, moisturized, in her lane. 😌

the following sections are informative — aka the bonus content, the DVD extras, the lore. 🙈

🍓 EXAMPLES 🍓

none. 🤷‍♀️

🧚 APPLICATION USAGE 🧚

none. 🤷‍♀️

🌸 RATIONALE 🌸

none. 🤷‍♀️

🦋 FUTURE DIRECTIONS 🦋

none. 🤷‍♀️ (we love a consistent queen)

⭐ SEE ALSO ⭐

  • fpclassify()
  • isfinite()
  • isnan()
  • isnormal()
  • signbit()

and also, from the Base Definitions volume of POSIX.1‐2017: <math.h> 💖

ok so legally we have to say this and we're gonna say it with our whole chest:

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 — she's the final boss, the main character, the one who decides. 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 (rip, not us). to report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html . 🐛

and that's the whole page bestie!! this was brought to you by IEEE/The Open Group, way back in 2017, and honestly? they ate. mwah. 💋 go check if your float is infinity and have the best day, ily!! 💖✨🎀🦋🌸💅🫶

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