The following functions determine whether a Unicode string is entirely in upper case. or entirely in lower case, or entirely in title case, or already case-folded.
Sets
*resultp to true if mapping NFD(s) to upper case is a no-op, or to false otherwise, and returns 0. Upon failure, returns -1 witherrnoset.
Sets
*resultp to true if mapping NFD(s) to lower case is a no-op, or to false otherwise, and returns 0. Upon failure, returns -1 witherrnoset.
Sets
*resultp to true if mapping NFD(s) to title case is a no-op, or to false otherwise, and returns 0. Upon failure, returns -1 witherrnoset.
Sets
*resultp to true if applying case folding to NFD(S) is a no-op, or to false otherwise, and returns 0. Upon failure, returns -1 witherrnoset.
The following functions determine whether case mappings have any effect on a Unicode string.
Sets
*resultp to true if case matters for s, that is, if mapping NFD(s) to either upper case or lower case or title case is not a no-op. Set*resultp to false if NFD(s) maps to itself under the upper case mapping, under the lower case mapping, and under the title case mapping; in other words, when NFD(s) consists entirely of caseless characters. Upon failure, returns -1 witherrnoset.