package defs

func Fprintln(w io.Writer, a ...interface{}) (n int, err error)

// Writer is the interface that wraps the basic Write method.
//
// Write writes len(p) bytes from p to the underlying data stream. It
// returns the number of bytes written from p (0 <= n <= len(p)) and any
// error encountered that caused the write to stop early. Write must return
// a non-nil error if it returns n < len(p).
type Writer interface {
	Write(p []byte) (n int, err error)
}

// Reader is the interface that wraps the basic Read method.
//
// Read reads up to len(p) bytes into p.  It returns the number of bytes
// read (0 <= n <= len(p)) and any error encountered.  Even if Read
// returns n < len(p), it may use all of p as scratch space during the call.
// If some data is available but not len(p) bytes, Read conventionally
// returns what is available instead of waiting for more.
//
// When Read encounters an error or end-of-file condition after
// successfully reading n > 0 bytes, it returns the number of
// bytes read.  It may return the (non-nil) error from the same call
// or return the error (and n == 0) from a subsequent call.
// An instance of this general case is that a Reader returning
// a non-zero number of bytes at the end of the input stream may
// return either err == EOF or err == nil.  The next Read should
// return 0, EOF regardless.
//
// Callers should always process the n > 0 bytes returned before
// considering the error err.  Doing so correctly handles I/O errors
// that happen after reading some bytes and also both of the
// allowed EOF behaviors.
type Reader interface {
	Read(p []byte) (n int, err error)
}

// ReadWriter is the interface that groups the basic Read and Write methods.
type ReadWriter interface {
	Reader
	// contains filtered or unexported methods
}

// ReadCloser is the interface that groups the basic Read and Close methods.
type ReadCloser interface {
	Reader
	// contains filtered or unexported methods
}

// ReadWriteCloser is the interface that groups the basic Read, Write and Close methods.
type ReadWriteCloser interface {
	Reader
	// contains filtered or unexported methods
}

// ReadSeeker is the interface that groups the basic Read and Seek methods.
type ReadSeeker interface {
	Reader
	// contains filtered or unexported methods
}

// ReadWriteSeeker is the interface that groups the basic Read, Write and Seek methods.
type ReadWriteSeeker interface {
	Reader
	// contains filtered or unexported methods
}

type Conn interface {
	Read(b []byte) (n int, err error)
	Write(b []byte) (n int, err error)
	Close() error
	// ... some additional methods omitted ...
}

// Copy copies from src to dst until either EOF is reached
// on src or an error occurs.  It returns the number of bytes
// copied and the first error encountered while copying, if any.
func Copy(dst Writer, src Reader) (written int64, err error)