wcsncasecmp man page

wcsncasecmp — compare two fixed-size wide-character strings, ignoring case


#include <wchar.h>

int wcsncasecmp(const wchar_t *s1, const wchar_t *s2, size_t n);

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


Since glibc 2.10:

_POSIX_C_SOURCE >= 200809L

Before glibc 2.10:



The wcsncasecmp() function is the wide-character equivalent of the strncasecmp(3) function. It compares the wide-character string pointed to by s1 and the wide-character string pointed to by s2, but at most n wide characters from each string, ignoring case differences (towupper(3), towlower(3)).

Return Value

The wcsncasecmp() function returns zero if the wide-character strings at s1 and s2, truncated to at most length n, are equal except for case distinctions. It returns a positive integer if truncated s1 is greater than truncated s2, ignoring case. It returns a negative integer if truncated s1 is smaller than truncated s2, ignoring case.


The wcsncasecmp() function is provided in glibc since version 2.1.


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

Interface Attribute Value
wcsncasecmp() Thread safety MT-Safe locale

Conforming to

POSIX.1-2008. This function is not specified in POSIX.1-2001, and is not widely available on other systems.


The behavior of wcsncasecmp() depends on the LC_CTYPE category of the current locale.

See Also

strncasecmp(3), wcsncmp(3)


This page is part of release 4.09 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

Referenced By

strcasecmp(3), wcsncmp(3).

2016-03-15 GNU Linux Programmer's Manual