UNICODE_CATEGORY_LOO(3)

💖 UNICODE_CATEGORY_LOO(3) 💖

okay bestie, welcome to the UNICODE_CATEGORY_LOO(3) page from the Courier Unicode Library — yes the whole page is literally about figuring out what kind of character you're looking at, and honestly? iconic. let's get into it 🦋

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✨ NAME ✨

unicode_category_lookup, unicode_isalnum, unicode_isalpha, unicode_isblank, unicode_isdigit, unicode_isgraph, unicode_islower, unicode_ispunct, unicode_isspace, unicode_isupper — unicode character categorization 💅

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🌸 SYNOPSIS 🌸

#include <courier-unicode.h>

uint32_t unicode_category_lookup(char32_t c);

int unicode_isalnum(char32_t c);

int unicode_isalpha(char32_t c);

int unicode_isblank(char32_t c);

int unicode_isdigit(char32_t c);

int unicode_isgraph(char32_t c);

int unicode_islower(char32_t c);

int unicode_ispunct(char32_t c);

int unicode_isspace(char32_t c);

int unicode_isupper(char32_t c);

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👑 DESCRIPTION 👑

so unicode_category_lookup() is the main character here: it looks up the unicode character's categorization[1]. and it hands you back a 32 bit value, no cap.

the way that value works: its UNICODE_CATEGORY_1 bits tell you the first level of the unicode character's category. then UNICODE_CATEGORY_2, UNICODE_CATEGORY_3, and UNICODE_CATEGORY_4 bits specify the 2nd, 3rd, and 4th level, if given. 💫

if the bits for a level are all set to 0, that means no category is specified for this level, for this character. otherwise, the possible values live in <courier-unicode.h> 📁

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🎀 the rest of the girlies 🎀

these ones are the unicode glow-up of their non-unicode versions in the standard C library, fr fr:

• unicode_isalnum() — returns non-0 for all unicode_isalpha() or unicode_isdigit(). basically "is it a letter OR a number" energy ✨
• unicode_isalpha() — returns non-0 for all UNICODE_CATEGORY_1_LETTER. letters only, periodt 🔤
• unicode_isblank() — returns non-0 for TAB, and all UNICODE_CATEGORY_2_SPACE 🫧
• unicode_isdigit() — returns non-0 for all UNICODE_CATEGORY_1_NUMBER | UNICODE_CATEGORY_2_DIGIT, only — no third categories bestie, that's the whole vibe 🔢
• unicode_isgraph() — returns non-0 for all codepoints above SPACE which are not unicode_isspace() 💀
• unicode_islower() — returns non-0 for all unicode_isalpha() for which the character is equal to unicode_lc(3) of itself. lowercase girlies rise 🥰
• unicode_ispunct() — returns non-0 for all UNICODE_CATEGORY_1_PUNCTUATION ❗❓‼️
• unicode_isspace() — returns non-0 for unicode_isblank() or for unicode characters with linebreaking properties of BK, CR, LF, NL, and SP 🌀
• unicode_isupper() — returns non-0 for all unicode_isalpha() for which the character is equal to unicode_uc(3) of itself. uppercase icon behavior 👑

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🔥 SEE ALSO 🔥

• courier-unicode(7)
• unicode_convert_tocase(3)

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💜 AUTHOR 💜

Sam Varshavchik

• Author 🫶

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🍓 NOTES 🍓

1. unicode character's categorization https://unicode.org/notes/tn36/

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okay that's the whole page, you ate that 🧚✨ and for the sign-off: this lovely lil manual page is from the Courier Unicode Library, dated 04/12/2026 — go forth and categorize ur characters responsibly bestie, mwah 💖🌈🌸