seek
This method moves the stream offset of the steam implementing this
interface.
@throws NS_BASE_STREAM_CLOSED if called on a closed stream.
| whence | specifies how to interpret the 'offset' parameter in setting the stream offset associated with the implementing stream. |
| offset | specifies a value, in bytes, that is used in conjunction with the 'whence' parameter to set the stream offset of the implementing stream. A negative value causes seeking in the reverse direction. |
tell
This method reports the current offset, in bytes, from the start of the
stream.
@throws NS_BASE_STREAM_CLOSED if called on a closed stream.
setEOF
This method truncates the stream at the current offset.
@throws NS_BASE_STREAM_CLOSED if called on a closed stream.