pub trait SeekableExt:
IsA<Seekable>
+ Sealed
+ 'static {
// Provided methods
fn can_seek(&self) -> bool { ... }
fn can_truncate(&self) -> bool { ... }
fn seek(
&self,
offset: i64,
type_: SeekType,
cancellable: Option<&impl IsA<Cancellable>>,
) -> Result<(), Error> { ... }
fn tell(&self) -> i64 { ... }
fn truncate(
&self,
offset: i64,
cancellable: Option<&impl IsA<Cancellable>>,
) -> Result<(), Error> { ... }
}
Expand description
Trait containing all Seekable
methods.
§Implementors
BufferedInputStream
, BufferedOutputStream
, DataInputStream
, DataOutputStream
, FileIOStream
, FileInputStream
, FileOutputStream
, MemoryInputStream
, MemoryOutputStream
, Seekable
Provided Methods§
Sourcefn can_truncate(&self) -> bool
fn can_truncate(&self) -> bool
Sourcefn seek(
&self,
offset: i64,
type_: SeekType,
cancellable: Option<&impl IsA<Cancellable>>,
) -> Result<(), Error>
fn seek( &self, offset: i64, type_: SeekType, cancellable: Option<&impl IsA<Cancellable>>, ) -> Result<(), Error>
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 None
, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation
was cancelled, the error IOErrorEnum::Cancelled
will be returned.
§offset
a #goffset.
§type_
a #GSeekType.
§cancellable
optional #GCancellable object, None
to ignore.
§Returns
true
if successful. If an error
has occurred, this function will return false
and set @error
appropriately if present.
Sourcefn tell(&self) -> i64
fn tell(&self) -> i64
Tells the current position within the stream.
§Returns
the (positive or zero) offset from the beginning of the buffer, zero if the target is not seekable.
Sourcefn truncate(
&self,
offset: i64,
cancellable: Option<&impl IsA<Cancellable>>,
) -> Result<(), Error>
fn truncate( &self, offset: i64, cancellable: Option<&impl IsA<Cancellable>>, ) -> Result<(), Error>
Sets the length of the stream to @offset. If the stream was previously larger than @offset, the extra data is discarded. If the stream was previously shorter than @offset, it is extended with NUL (‘\0’) bytes.
If @cancellable is not None
, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation
was cancelled, the error IOErrorEnum::Cancelled
will be returned. If an
operation was partially finished when the operation was cancelled the
partial result will be returned, without an error.
§offset
new length for @self, in bytes.
§cancellable
optional #GCancellable object, None
to ignore.
§Returns
true
if successful. If an error
has occurred, this function will return false
and set @error
appropriately if present.
Dyn Compatibility§
This trait is not dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.