ISWCNTRL(3P)

💖 ISWCNTRL(3P) 💖

okay bestie, we're in the POSIX Programmer's Manual rn — section 3P, the whole POSIX Programmer's Manual vibe — and this page is literally all about asking the universe "is this wide character a control character or not". ✨

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🌸 PROLOG 🌸

so, real talk, this manual page is part of the POSIX Programmer's Manual. the Linux implementation of this interface may differ — like, consult the corresponding Linux manual page for the deets on Linux behavior — or honestly the interface might not even be implemented on Linux at all. 😭 so don't come for me if it's not there.

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✨ NAME ✨

iswcntrl, iswcntrl_l — test for a control wide-character code 🎀

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🦋 SYNOPSIS 🦋

#include <wctype.h>

int iswcntrl(wint_t wc);
int iswcntrl_l(wint_t wc, locale_t locale);

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👑 DESCRIPTION 👑

For iswcntrl(): 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 — like, we did not mean to do that. this volume of POSIX.1‐2017 defers to the ISO C standard, periodt.

the iswcntrl() and iswcntrl_l() functions shall test whether wc is a wide-character code representing a character of class cntrl 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 — 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 being dramatic, that's just what it says 💀

🚨 bestie listen: the behavior is undefined if the locale argument to iswcntrl_l() is the special locale object LC_GLOBAL_LOCALE or is not a valid locale object handle. don't do it. fr fr.

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🌈 RETURN VALUE 🌈

iswcntrl() and iswcntrl_l() shall return non-zero if wc is a control wide-character code; otherwise, they shall return 0. that's it, that's the whole answer. slay. 💅

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💜 ERRORS 💜

no errors are defined. iconic, honestly — nothing to see here. 🎀

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 — 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 assignment, no substitutions. ✨

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🧠 RATIONALE 🧠

none.

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🦄 FUTURE DIRECTIONS 🦄

none.

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💖 SEE ALSO 💖

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

also the Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale, <locale.h>, <wctype.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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and that's the whole page, bestie 🫶 — brought to you by IEEE/The Open Group, 2017, ISWCNTRL(3P). go forth and classify your wide characters responsibly 💅✨