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