package sftp import (	"io"	"os") // Interfaces are differentiated based on required returned values.// All input arguments are to be pulled from Request (the only arg). // The Handler interfaces all take the Request object as its only argument.// All the data you should need to handle the call are in the Request object.// The request.Method attribute is initially the most important one as it// determines which Handler gets called. // FileReader should return an io.ReaderAt for the filepath// Note in cases of an error, the error text will be sent to the client.// Called for Methods: Gettype FileReader interface {	Fileread(*Request) (io.ReaderAt, error)} // FileWriter should return an io.WriterAt for the filepath.//// The request server code will call Close() on the returned io.WriterAt// ojbect if an io.Closer type assertion succeeds.// Note in cases of an error, the error text will be sent to the client.// Note when receiving an Append flag it is important to not open files using// O_APPEND if you plan to use WriteAt, as they conflict.// Called for Methods: Put, Opentype FileWriter interface {	Filewrite(*Request) (io.WriterAt, error)} // FileCmder should return an error// Note in cases of an error, the error text will be sent to the client.// Called for Methods: Setstat, Rename, Rmdir, Mkdir, Link, Symlink, Removetype FileCmder interface {	Filecmd(*Request) error} // FileLister should return an object that fulfils the ListerAt interface// Note in cases of an error, the error text will be sent to the client.// Called for Methods: List, Stat, Readlinktype FileLister interface {	Filelist(*Request) (ListerAt, error)} // ListerAt does for file lists what io.ReaderAt does for files.// ListAt should return the number of entries copied and an io.EOF// error if at end of list. This is testable by comparing how many you// copied to how many could be copied (eg. n < len(ls) below).// The copy() builtin is best for the copying.// Note in cases of an error, the error text will be sent to the client.type ListerAt interface {	ListAt([]os.FileInfo, int64) (int, error)} // TransferError is an optional interface that readerAt and writerAt// can implement to be notified about the error causing Serve() to exit// with the request still opentype TransferError interface {	TransferError(err error)}