ISWSPACE(3P)

💖 ISWSPACE(3P) — the POSIX Programmer's Manual glow-up 💖

okay bestie, before we even get into it: this page lives in the POSIX Programmer's Manual, which is its whole ~thing~. Important heads up tho — the Linux implementation of this interface may differ, so if you're on Linux you gotta peek at the matching Linux manual page for the real tea. And lowkey it's possible the interface just... isn't implemented on Linux at all. 🙈 So vibe check your system first.

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✨ PROLOG ✨

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

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🌸 NAME 🌸

iswspace, iswspace_l — test for a white-space wide-character code

it's giving "is this wide char a space or nah" and honestly? iconic job description.

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🎀 SYNOPSIS 🎀

#include <wctype.h>

int iswspace(wint_t wc);
int iswspace_l(wint_t wc, locale_t locale);

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🦋 DESCRIPTION 🦋

so for iswspace(): the functionality on this reference page is aligned with the ISO C standard, periodt. If there's any conflict between the requirements written here and the ISO C standard, that conflict is unintentional — and this volume of POSIX.1‐2017 defers to the ISO C standard. C is the main character here, we're just supporting cast. 💅

The iswspace() and iswspace_l() functions shall test whether wc is a wide-character code representing a character of class space in the current locale, or in the locale represented by locale, respectively. (Yeah, that second one is the whole point of the _l version — you get to pick the locale yourself instead of just going with whatever the current one is. iykyk.) See the Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale for the deets.

Now the wc argument: it's a wint_t, and the value of it — your application shall ensure — is a wide-character code corresponding to a valid character in the locale used by the function, or equal to the value of the macro WEOF. If the argument has any other value?? the behavior is undefined. not "a little weird", not "whatever", undefined. don't do it bestie. 😭

🚨 also undefined behavior alert: if the locale argument to iswspace_l() is the special locale object LC_GLOBAL_LOCALE, or is not a valid locale object handle — yeah, undefined. No cap. Do not pass those in.

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💫 RETURN VALUE 💫

The iswspace() and iswspace_l() functions shall return non-zero if wc is a white-space wide-character code; otherwise, they shall return 0.

that's it. that's the whole vibe. truthy = space, 0 = not space. 🫶

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🌈 ERRORS 🌈

No errors are defined.

(the following sections are informative, btw 👇)

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⭐ EXAMPLES ⭐

None.

we literally have zero examples. nothing. empty. the void. 💀

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💜 APPLICATION USAGE 💜

To ensure applications portability — especially across natural languages — only these functions and the functions in the reference pages listed in the SEE ALSO section should be used for character classification. so like, stay in the family, don't go rogue with your own classification logic. 🌍✨

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🧚 RATIONALE 🧚

None.

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🌸 FUTURE DIRECTIONS 🌸

None.

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👑 SEE ALSO 👑

• iswalnum()
• iswalpha()
• iswcntrl()
• iswctype()
• iswdigit()
• iswgraph()
• iswlower()
• iswprint()
• iswpunct()
• iswupper()
• iswxdigit()
• setlocale()
• uselocale()

Also the Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale, <locale.h>, and <wctype.h>. the whole friend group, 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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and that's a wrap, bestie!! this lil masterpiece came to you courtesy of IEEE/The Open Group, 2017 — the ISWSPACE(3P) energy we all needed. go check your wide chars, stay in your locale, and never ever pass an invalid handle. mwah. 💖✨🎀🦋🌸💅🫶