Function tokio::io::copy [−][src]
pub fn copy<'a, R: ?Sized, W: ?Sized>(
reader: &'a mut R,
writer: &'a mut W
) -> Copy<'a, R, W>ⓘ where
R: AsyncRead + Unpin,
W: AsyncWrite + Unpin,
Asynchronously copies the entire contents of a reader into a writer.
This function returns a future that will continuously read data from
reader
and then write it into writer
in a streaming fashion until
reader
returns EOF.
On success, the total number of bytes that were copied from reader
to
writer
is returned.
This is an asynchronous version of std::io::copy
.
Errors
The returned future will finish with an error will return an error
immediately if any call to poll_read
or poll_write
returns an error.
Examples
use tokio::io; let mut reader: &[u8] = b"hello"; let mut writer: Vec<u8> = vec![]; io::copy(&mut reader, &mut writer).await?; assert_eq!(&b"hello"[..], &writer[..]);