wcslen(3)

💖 wcslen(3) — bestie, let's count some wide characters 💖

okay so this is the wcslen page from the library functions manual and honestly? she's a little icon. tiny function, big main character energy. let's get into it 🫶

✨ NAME ✨

wcslen — figure out how long a wide-character string is 🌸

📚 LIBRARY 📚

Standard C library (libc, -lc) 💅

🎀 SYNOPSIS 🎀

#include <wchar.h>

size_t wcslen(const wchar_t *s);

🦋 DESCRIPTION 🦋

So. wcslen() is the wide-character glow-up of strlen(3) — literally the same vibe, just built for wide characters instead of plain ones. no cap.

What she does: she determines the length of the wide-character string that s is pointing at. and bestie, listen — she does not count the terminating null wide character, L'\0'. that one gets left out. she counts up to it and stops, like a respectful queen. 👑

💫 RETURN VALUE 💫

wcslen() returns the number of wide characters in s. that's it. that's the whole answer. periodt. ✨

🔥 ATTRIBUTES 🔥

ngl if you wanna know what all these terms even mean, go check out attributes(7) — she explains it properly.

• wcslen() — Thread safety: MT-Safe 🌈

fr fr, MT-Safe means she's safe to call from multiple threads at once, no drama 💀

👑 STANDARDS 👑

This baddie is standardized in C11 and POSIX.1-2008. ate. 💅

🌸 HISTORY 🌸

She's been around: POSIX.1-2001, C99. iconic since forever. 🎀

⭐ NOTES ⭐

okay this part actually matters so pay attention bestie 🙈

If there's a chance your input buffer does not contain a terminating null wide character, you should be using wcsnlen(3) instead. like, do not just rawdog wcslen() on a buffer that might not be null-terminated. she will keep walking and walking and walking and it's giving undefined behavior 😭

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🫶 SEE ALSO 🫶

• strlen(3)

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and that's the page!! <rainbow>wcslen(3)</rainbow> came from Linux man-pages 6.20, dated 2026-02-08 — ty for the docs, slay, mwah 💖✨🦋