wcsnlen(3)

wcsnlen3

Determine the length of a fixed-size wide-character string

Usage

#include <wchar.h>

size_t wcsnlen(const wchar_t s[], size_t maxlen);

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

wcsnlen():

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

Library

Standard C library (libc, -lc)

Overview

The wcsnlen() function is the wide-character equivalent of the strnlen(3) function. It returns the number of wide-characters in the string pointed to by s, not including the terminating null wide character (L'\0'), but at most maxlen wide characters (note: this parameter is not a byte count). In doing this, wcsnlen() looks at only the first maxlen wide characters at s and never beyond s[maxlen-1].

Return value

The wcsnlen() function returns wcslen(s), if that is less than maxlen, or maxlen if there is no null wide character among the first maxlen wide characters pointed to by s.

Attributes

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

InterfaceAttributeValue
wcsnlen()Thread safetyMT-Safe

Releases

14 releases since Debian 2.2 (Potato); the text changed 13 times.

  1. 2.2
  2. 3.0
  3. 3.1
  4. 4.0
  5. 5.0
  6. 6.0
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. Arch

Standards

POSIX.1-2008.

History

glibc 2.1.

From man-pages 6.19-1 in Arch Linux 2026-11-01. Parsed by carta from the page's man source.