The file system of a hard disk or optical disc may lose consistency when an unexpected event like a power failure occurs during recording. When recording a data stream, e.g. a video stream, an interruption would lead to a loss of stream data when previously known methods are used, because the file system is not updated. Further, the storage medium may become unusable. Dedicated file system data are put in regular intervals in user data fields of the data stream, providing the possibility to recover an interrupted stream recording. The method can also be used to recover data streams recorded on write-once discs, and it is independent from the used file system.