Trait tokio::io::AsyncSeek  [−][src]
pub trait AsyncSeek {
    fn start_seek(
        self: Pin<&mut Self>, 
        cx: &mut Context<'_>, 
        position: SeekFrom
    ) -> Poll<Result<()>>;
    fn poll_complete(
        self: Pin<&mut Self>, 
        cx: &mut Context<'_>
    ) -> Poll<Result<u64>>;
}Seek bytes asynchronously.
This trait is analogous to the std::io::Seek trait, but integrates
with the asynchronous task system. In particular, the start_seek
method, unlike Seek::seek, will not block the calling thread.
Utilities for working with AsyncSeek values are provided by
AsyncSeekExt.
Required methods
fn start_seek(
    self: Pin<&mut Self>, 
    cx: &mut Context<'_>, 
    position: SeekFrom
) -> Poll<Result<()>>[src]
self: Pin<&mut Self>,
cx: &mut Context<'_>,
position: SeekFrom
) -> Poll<Result<()>>
Attempts to seek to an offset, in bytes, in a stream.
A seek beyond the end of a stream is allowed, but behavior is defined by the implementation.
If this function returns successfully, then the job has been submitted.
To find out when it completes, call poll_complete.
fn poll_complete(
    self: Pin<&mut Self>, 
    cx: &mut Context<'_>
) -> Poll<Result<u64>>[src]
self: Pin<&mut Self>,
cx: &mut Context<'_>
) -> Poll<Result<u64>>
Waits for a seek operation to complete.
If the seek operation completed successfully,
this method returns the new position from the start of the stream.
That position can be used later with SeekFrom::Start.
Errors
Seeking to a negative offset is considered an error.
Panics
Calling this method without calling start_seek first is an error.
Implementations on Foreign Types
impl<T: ?Sized + AsyncSeek + Unpin> AsyncSeek for Box<T>[src]
impl<T: ?Sized + AsyncSeek + Unpin> AsyncSeek for Box<T>[src]impl<T: ?Sized + AsyncSeek + Unpin> AsyncSeek for &mut T[src]
impl<T: ?Sized + AsyncSeek + Unpin> AsyncSeek for &mut T[src]impl<P> AsyncSeek for Pin<P> where
    P: DerefMut + Unpin,
    P::Target: AsyncSeek, [src]
impl<P> AsyncSeek for Pin<P> where
    P: DerefMut + Unpin,
    P::Target: AsyncSeek, [src]impl<T: AsRef<[u8]> + Unpin> AsyncSeek for Cursor<T>[src]
impl<T: AsRef<[u8]> + Unpin> AsyncSeek for Cursor<T>[src]