ISWALNUM(3)

💖 ISWALNUM(3) 💖

okay bestie, this is the Library Functions Manual entry for ISWALNUM(3) — wide-character classification, but make it fashion. 💅

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✨ NAME ✨

iswalnum, iswalpha, iswascii, iswblank, iswcntrl, iswdigit, iswgraph, iswhexnumber, iswideogram, iswlower, iswnumber, iswphonogram, iswprint, iswpunct, iswrune, iswspace, iswspecial, iswupper, iswxdigit — wide character classification utilities 🦋

🎀 LIBRARY 🎀

Standard C Library (libc, -lc) — yes bestie, link it with -lc and you're slaying. ✨

🌈 SYNOPSIS 🌈

every single one of these takes a wint_t wc and returns int, no cap. pull in the header like this:

#include <wctype.h>

int
iswalnum(wint_t wc);

int
iswalpha(wint_t wc);

int
iswascii(wint_t wc);

int
iswblank(wint_t wc);

int
iswcntrl(wint_t wc);

int
iswdigit(wint_t wc);

int
iswgraph(wint_t wc);

int
iswhexnumber(wint_t wc);

int
iswideogram(wint_t wc);

int
iswlower(wint_t wc);

int
iswnumber(wint_t wc);

int
iswphonogram(wint_t wc);

int
iswprint(wint_t wc);

int
iswpunct(wint_t wc);

int
iswrune(wint_t wc);

int
iswspace(wint_t wc);

int
iswspecial(wint_t wc);

int
iswupper(wint_t wc);

int
iswxdigit(wint_t wc);

🦋 DESCRIPTION 🦋

The above functions are character classification utility functions, for use with wide characters (wchar_t or wint_t). See the description for the similarly-named single byte classification functions (like isalnum(3)), for details.

like, they're the wide-character girlies — same classification energy, but for wchar_t and wint_t. for the full deets, go read the matching single-byte function descriptions like isalnum(3). iykyk 💜

💜 RETURN VALUES 💜

The functions return zero if the character tests false and return non-zero if the character tests true.

so: false = 0, true = not-0. slay. ✨

👑 SEE ALSO 👑

go read these next, bestie:

• isalnum(3)
• isalpha(3)
• isascii(3)
• isblank(3)
• iscntrl(3)
• isdigit(3)
• isgraph(3)
• ishexnumber(3)
• isideogram(3)
• islower(3)
• isnumber(3)
• isphonogram(3)
• isprint(3)
• ispunct(3)
• isrune(3)
• isspace(3)
• isspecial(3)
• isupper(3)
• isxdigit(3)
• wctype(3)

🌟 STANDARDS 🌟

These functions conform to IEEE Std 1003.1-2001 (“POSIX.1”), except iswascii(), iswhexnumber(), iswideogram(), iswnumber(), iswphonogram(), iswrune() and iswspecial(), which are FreeBSD extensions. 🫶

⚠️ CAVEATS ⚠️

undefined behavior alert 🚨 The result of these functions is undefined unless the argument is WEOF or a valid wchar_t value for the current locale. please don't test the universe, bestie 😭

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mwah 💋 this page is from the Debian source/version, dated October 3, 2002, and it's the ISWALNUM(3) manual page. periodt. 🫶