Interpretation of Multibyte-Character Sequences
Most multibyte-character routines in the Microsoft run-time library recognize multibyte-character sequences relating to a multibyte code page. The output value is affected by the setting of the LC_CTYPE category setting of the locale; see setlocale for more information. The versions of these functions without the _l suffix use the current locale for this locale-dependent behavior; the versions with the _l suffix are identical except that they use the locale parameter passed in instead.
Validate and return number of bytes in multibyte character
For multibyte character strings: validate each character in string; return string length. For wide character strings: return string length.
Convert sequence of multibyte characters to corresponding sequence of wide characters
Convert multibyte character to corresponding wide character
Convert sequence of wide characters to corresponding sequence of multibyte characters
Convert wide character to corresponding multibyte character