MB_LEN_MAX (3) - Linux Man Pages
MB_LEN_MAX: maximum multibyte length of a character across all locales
MB_LEN_MAX - maximum multibyte length of a character across all locales
DESCRIPTIONThe MB_LEN_MAX macro is the maximum number of bytes needed to represent a single wide character, in any of the supported locales.
RETURN VALUEA constant integer greater than zero.
CONFORMING TOPOSIX.1-2001, POSIX.1-2008, C99.
NOTESThe entities MB_LEN_MAX and sizeof(wchar_t) are totally unrelated. In glibc, MB_LEN_MAX is typically 16 (6 in glibc versions earlier than 2.2), while sizeof(wchar_t) is 4.
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