wcsdup(3)

✨ wcsdup(3) ✨

okay bestie, so this is <wchar.h>'s resident copycat — the wide-character glow-up of strdup(3). 💖

🌸 NAME 🌸

wcsdup — duplicate a wide-character string 🦋

📚 LIBRARY 📚

Standard C library (libc, -lc) — the O.G. one you already link against, no cap.

✨ SYNOPSIS ✨

#include <wchar.h>

wchar_t *wcsdup(const wchar_t *s);

🎀 Feature Test Macro Requirements for glibc (see feature_test_macros(7)) 🎀

wcsdup():

• Since glibc 2.10:
  • _POSIX_C_SOURCE >= 200809L
• Before glibc 2.10:
  • _GNU_SOURCE

Like, if you're on ancient glibc and this won't compile, it's giving "you forgot _GNU_SOURCE". iykyk 💅

💖 DESCRIPTION 💖

The wcsdup() function is literally the wide-character equivalent of the strdup(3) function — same vibe, wider chars. It allocates and returns a new wide-character string whose initial contents is a duplicate of the wide-character string pointed to by s. 🫶

Memory for the new wide-character string is obtained with malloc(3), and should be freed with free(3). No leaking, bestie — that's not the main character energy we're going for. 🧚

🚨 reminder: it's malloc'd, so it's yours. free(3) it when you're done or it's just gonna sit there in your heap forever like an unread group chat. 😭

🌈 RETURN VALUE 🌈

On success, wcsdup() returns a pointer to the new wide-character string. Slay.

On error, it returns NULL, with errno set to indicate the error. Check it. Please. 🙈

💀 ERRORS 💀

• ENOMEM — Insufficient memory available to allocate duplicate string. The malloc said no. 💔

👑 ATTRIBUTES 👑

For an explanation of the terms used in this section, see attributes(7).

• wcsdup() — Thread safety: MT-Safe ✅

Thread safe babyyy, MT-Safe, you can call it from multiple threads and it will simply not be the drama. 🔥

⭐ STANDARDS ⭐

POSIX.1-2008. Periodt. Certified. 📜

🕰️ HISTORY 🕰️

libc5, glibc 2.0 — so it's been here since basically forever, an icon, a legend. 👑

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🔎 SEE ALSO 🔎

• strdup(3)
• wcscpy(3)

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k bye, love u, go free your strings 🫶 — this page came to you from Linux man-pages 6.20, dated 2026-02-08, and it's wcsdup(3) fr fr. 💜✨