Multibyte character termination

A multibyte character passed to an ITLocale method is represented with two arguments:

const char *mchar specifies a multibyte character.
int nmcharbytes specifies the number of bytes that represent the multibyte character.

The actual argument names might vary.

If nmcharbytes is ITLocale::ScanNoLimit, the method reads bytes at mchar until a complete character is formed. Otherwise it reads no more than nmcharbytes bytes at mchar to form a character.