formatted I/O

Input operations can be formatted or unformatted:


 * Formatted input typically skips leading whitespace and then reads one or more characters that conform to a prescribed format, setting the stream's failbit if input is malformed, and often leaving whitespace in the stream. Examples include overloaded >> input operators.
 * Unformatted input typically accepts one or more characters (including whitespace) up to some maximum number of characters or some particular value of character, setting the stream's failbit only if zero characters are read. Examples include istream::read, istream::get, istream::getline.
 * Formatted output writes any number of characters according to a prescribed format, setting the stream's badbit on failure. Examples include overloaded << output operators.
 * Unformatted output typically writes a fixed number of characters, setting the stream's badbit</tt> on error. Examples include ostream::write</tt>.