bool is_directory(file_status s) noexcept;
Returns: s.type() == file_type::directory. bool is_directory(const path& p);
bool is_directory(const path& p, error_code& ec) noexcept;
Returns: is_directory(status(p)) or
is_directory(status(p, ec)),
respectively
. The signature with argument
ec returns
false if an error occurs
.