// Cross platform errors package vfs import (	"fmt"	"os") // Error describes low level errors in a cross platform way.type Error byte // NB if changing errors translateError in cmd/mount/fs.go, cmd/cmount/fs.go // Low level errorsconst (	OK Error = iota	ENOTEMPTY	ESPIPE	EBADF	EROFS	ENOSYS) // Errors which have exact counterparts in osvar (	ENOENT = os.ErrNotExist	EEXIST = os.ErrExist	EPERM  = os.ErrPermission	EINVAL = os.ErrInvalid	// ECLOSED see errors_{old,new}.go) var errorNames = []string{	OK:        "Success",	ENOTEMPTY: "Directory not empty",	ESPIPE:    "Illegal seek",	EBADF:     "Bad file descriptor",	EROFS:     "Read only file system",	ENOSYS:    "Function not implemented",} // Error renders the error as a stringfunc (e Error) Error() string {	if int(e) >= len(errorNames) {		return fmt.Sprintf("Low level error %d", e)	}	return errorNames[e]}