_mbsnbicmp, _mbsnbicmp_l

Compares n bytes of two multibyte-character strings, and ignores case.

Important note Important

This API cannot be used in applications that execute in the Windows Runtime. For more information, see CRT functions not supported with /ZW.

int _mbsnbicmp(
   const unsigned char *string1,
   const unsigned char *string2,
   size_t count 

string1, string2

Null-terminated strings to compare.


Number of bytes to compare.

The return value indicates the relationship between the substrings.

Return value


< 0

string1 substring less than string2 substring.


string1 substring identical to string2 substring.

> 0

string1 substring greater than string2 substring.

On an error, _mbsnbcmp returns _NLSCMPERROR, which is defined in String.h and Mbstring.h.

The _mbsnbicmp function performs an ordinal comparison of at most the first count bytes of string1 and string2. The comparison is performed by converting each character to lowercase; _mbsnbcmp is a case-sensitive version of _mbsnbicmp. The comparison ends if a terminating null character is reached in either string before count characters are compared. If the strings are equal when a terminating null character is reached in either string before count characters are compared, the shorter string is lesser.

_mbsnbicmp is similar to _mbsnicmp, except that it compares strings up to count bytes instead of by characters.

Two strings containing characters located between 'Z' and 'a' in the ASCII table ('[', '\', ']', '^', '_', and '`') compare differently, depending on their case. For example, the two strings "ABCDE" and "ABCD^" compare one way if the comparison is lowercase ("abcde" > "abcd^") and the other way ("ABCDE" < "ABCD^") if it is uppercase.

_mbsnbicmp recognizes multibyte-character sequences according to the multibyte code page currently in use. It is not affected by the current locale setting.

If either string1 or string2 is a null pointer, _mbsnbicmp invokes the invalid parameter handler as described in Parameter Validation. If execution is allowed to continue, the function returns _NLSCMPERROR and sets errno to EINVAL.

Generic-Text Routine Mappings

Tchar.h routine

_UNICODE and _MBCS not defined

_MBCS defined

_UNICODE defined










Required header



For more compatibility information, see Compatibility.

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.