X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=gio%2Fgseekable.c;h=3d8959193d87bfe0dc9cb78c9cf04b98bca9569d;hb=4482977238ae80f64c2fe318d1500f4662c73980;hp=ac77b12e5a32d73da134735327099320ef1e833c;hpb=d85b722734a6fcfe94032f6113de9e5c190fd7c3;p=platform%2Fupstream%2Fglib.git diff --git a/gio/gseekable.c b/gio/gseekable.c index ac77b12..3d89591 100644 --- a/gio/gseekable.c +++ b/gio/gseekable.c @@ -13,9 +13,7 @@ * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General - * Public License along with this library; if not, write to the - * Free Software Foundation, Inc., 59 Temple Place, Suite 330, - * Boston, MA 02111-1307, USA. + * Public License along with this library; if not, see . * * Author: Alexander Larsson */ @@ -30,10 +28,21 @@ * @short_description: Stream seeking interface * @include: gio/gio.h * @see_also: #GInputStream, #GOutputStream - * - * #GSeekable is implemented by streams (implementations of + * + * #GSeekable is implemented by streams (implementations of * #GInputStream or #GOutputStream) that support seeking. - * + * + * Seekable streams largely fall into two categories: resizable and + * fixed-size. + * + * #GSeekable on fixed-sized streams is approximately the same as POSIX + * lseek() on a block device (for example: attmepting to seek past the + * end of the device is an error). Fixed streams typically cannot be + * truncated. + * + * #GSeekable on resizable streams is approximately the same as POSIX + * lseek() on a normal file. Seeking past the end and writing data will + * usually cause the stream to resize by introducing zero bytes. **/ typedef GSeekableIface GSeekableInterface; @@ -89,12 +98,21 @@ g_seekable_can_seek (GSeekable *seekable) * @seekable: a #GSeekable. * @offset: a #goffset. * @type: a #GSeekType. - * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. - * @error: a #GError location to store the error occurring, or %NULL to + * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. + * @error: a #GError location to store the error occurring, or %NULL to * ignore. - * + * * Seeks in the stream by the given @offset, modified by @type. * + * Attempting to seek past the end of the stream will have different + * results depending on if the stream is fixed-sized or resizable. If + * the stream is resizable then seeking past the end and then writing + * will result in zeros filling the empty space. Seeking past the end + * of a resizable stream and reading will result in EOF. Seeking past + * the end of a fixed-sized stream will fail. + * + * Any operation that would result in a negative offset will fail. + * * If @cancellable is not %NULL, then the operation can be cancelled by * triggering the cancellable object from another thread. If the operation * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.