ISWBLANK(3POSIX)

💖 ISWBLANK — the POSIX Programmer's Manual, but make it cute 💖

okay bestie, before anything else: this page lives inside the POSIX Programmer's Manual. That's the whole vibe. And a lil heads-up from the PROLOG, no cap: the Linux implementation of this interface may differ from what's written here (so like, go check the corresponding Linux manual page for the deets on Linux behavior), or honestly the interface might not even be implemented on Linux at all. 🙈

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✨ NAME ✨

iswblank, iswblank_l — test for a blank wide-character code 🎀

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🌸 SYNOPSIS 🌸

#include <wctype.h>

int iswblank(wint_t wc);
int iswblank_l(wint_t wc, locale_t locale);

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🦋 DESCRIPTION 🦋

So for iswblank(): the functionality described on this reference page is aligned with the ISO C standard. And if there's any conflict between the requirements written here and the ISO C standard? Totally unintentional, not a vibe, not on purpose. This volume of POSIX.1‐2017 defers to the ISO C standard. periodt.

The iswblank() and iswblank_l() functions shall test whether wc is a wide-character code representing a character of class blank in the current locale, or in the locale represented by locale, respectively. (See the Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale — iykyk. 💅)

The wc argument is a wint_t, and the value of it is something the 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 me letting you pass garbage though.

🚨 And the behavior is undefined if the locale argument to iswblank_l() is the special locale object LC_GLOBAL_LOCALE, or if it's not a valid locale object handle. Like, don't do that. Fr fr.

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⭐ RETURN VALUE ⭐

The iswblank() and iswblank_l() functions shall return non-zero if wc is a blank wide-character code; otherwise, they shall return 0. Simple as that, bestie. 💖

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🌈 ERRORS 🌈

No errors are defined. Literally none. Iconic behavior honestly.

The following sections are informative.

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🍓 EXAMPLES 🍓

None.

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💜 APPLICATION USAGE 💜

To ensure applications portability — especially across natural languages, which is such a main character concern — only these functions and the functions in the reference pages listed in the SEE ALSO section should be used for character classification. That's the whole assignment. 🫶

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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()
• iswspace()
• iswupper()
• iswxdigit()
• setlocale()
• uselocale()

Also the Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale, plus <locale.h> and <wctype.h>. Go read those too, they ate. ✨

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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 the whole page, bestie!! 🦋💅 this edition was served to you by IEEE/The Open Group, 2017 — yeah, ISWBLANK(3POSIX), the one and only. go classify some blanks responsibly. mwah. 💖