You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: connection.go
    path of file: ./repos/rclone/cmd/serve/sftp
    
    the code of the file until where you have to start completion: //go:build !plan9
// +build !plan9

package sftp

import (
	"context"
	"errors"
	"fmt"
	"io"
	"net"
	"os"
	"regexp"
	"strings"

	"github.com/pkg/sftp"
	"github.com/rclone/rclone/
    
func serveChannel(rwc io.ReadWriteCloser, h sftp.Handlers, what string) error {
	fs.Debugf(what, "Starting SFTP server")
	server := sftp.NewRequestServer(rwc, h)
	defer func() {
		err := server.Close()
		if err != nil && err != io.EOF {
			fs.Debugf(what, "Failed to close server: %v", err)
		}
	}()
	err := server.Serve()
	if err != nil && err != io.EOF {
		return fmt.Errorf("completed with error: %w", err)
	}
	fs.Debugf(what, "exited session")
	return nil
}