4.io.go_ReaderWrite接口&其它

// ReadWriter is the interface that groups the basic Read and Write methods.
type ReadWriter interface {
	Reader
	Writer
}

// ReadCloser is the interface that groups the basic Read and Close methods.
type ReadCloser interface {
	Reader
	Closer
}

// WriteCloser is the interface that groups the basic Write and Close methods.
type WriteCloser interface {
	Writer
	Closer
}

// ReadWriteCloser is the interface that groups the basic Read, Write and Close methods.
type ReadWriteCloser interface {
	Reader
	Writer
	Closer
}

// ReadSeeker is the interface that groups the basic Read and Seek methods.
type ReadSeeker interface {
	Reader
	Seeker
}

// WriteSeeker is the interface that groups the basic Write and Seek methods.
type WriteSeeker interface {
	Writer
	Seeker
}

// ReadWriteSeeker is the interface that groups the basic Read, Write and Seek methods.
type ReadWriteSeeker interface {
	Reader
	Writer
	Seeker
}

这一套接口看上去琳琅满目的，其实仔细一看的话，无非就是
Reader
Writer
Closer
Seeker
四个的排列组合，是不是很简单，这一课就学完了。