Trait FileReader 

pub trait FileReader: Send {
    // Required methods
    fn read<B: IoBufMut>(
        &mut self,
        buffer: B,
        cancellation: &Cancellation,
    ) -> impl Future<Output = BufferResult<B>> + Send;
    fn read_at<B: IoBufMut>(
        &mut self,
        buffer: B,
        offset: u64,
        cancellation: &Cancellation,
    ) -> impl Future<Output = BufferResult<B>> + Send;
    fn close(&mut self) -> impl Future<Output = Result<()>> + Send;

    // Provided methods
    fn read_submit<B: IoBufMut>(
        &mut self,
        buffer: B,
        cancellation: &Cancellation,
    ) -> impl Future<Output = Result<impl Future<Output = BufferResult<B>> + Send + 'static, (OperationError, B)>> + Send { ... }
    fn read_at_submit<B: IoBufMut>(
        &mut self,
        buffer: B,
        offset: u64,
        cancellation: &Cancellation,
    ) -> impl Future<Output = Result<impl Future<Output = BufferResult<B>> + Send + 'static, (OperationError, B)>> + Send { ... }
}

Scheduler-bound, sequential access to a file’s readable direction. Construct through FileReading. Separate handles permit overlapping operations, but shared-cursor operations have no ordering guarantee across handles.

Required Methods

fn read<B: IoBufMut>( &mut self, buffer: B, cancellation: &Cancellation, ) -> impl Future<Output = BufferResult<B>> + Send

Read once at the file’s shared OS cursor, returning a possibly short count and the original owner on every result. Cancellation cannot roll back transferred bytes or cursor changes.

fn read_at<B: IoBufMut>( &mut self, buffer: B, offset: u64, cancellation: &Cancellation, ) -> impl Future<Output = BufferResult<B>> + Send

Read once at an explicit offset. Offsets must fit in i64. Unix implementations leave the shared cursor unchanged; Windows implementations may use seek_read, which changes it. The handle maintains no private cursor.

fn close(&mut self) -> impl Future<Output = Result<()>> + Send

Stop admission and await accepted operation retirement without cancellation. Repeated close is safe; dropping a pending close is not a retirement barrier. This does not close the underlying file. Drop the retired handle before exclusive file close.

Provided Methods

fn read_submit<B: IoBufMut>( &mut self, buffer: B, cancellation: &Cancellation, ) -> impl Future<Output = Result<impl Future<Output = BufferResult<B>> + Send + 'static, (OperationError, B)>> + Send

Await admission separately from collecting the original owner. Accepted work can complete independently of polling the returned future. The fallback completes the ordinary operation before returning; backends can admit independently progressing work earlier. Pre-cancellation rejects admission and returns the unchanged owner.

fn read_at_submit<B: IoBufMut>( &mut self, buffer: B, offset: u64, cancellation: &Cancellation, ) -> impl Future<Output = Result<impl Future<Output = BufferResult<B>> + Send + 'static, (OperationError, B)>> + Send

Await admission separately from collecting the original owner. Accepted work can complete independently of polling the returned future. The fallback completes the ordinary operation before returning; backends can admit independently progressing work earlier. Pre-cancellation rejects admission and returns the unchanged owner.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors