Function copy

pub async fn copy<R, W>(reader: R, writer: W) -> Result<u64>
where
    R: AsyncRead + Unpin,
    W: AsyncWrite + Unpin,

Copies the entire contents of a reader into a writer.

This function will read data from reader and write it into writer in a streaming fashion until reader returns EOF.

On success, returns the total number of bytes copied.

Examples

use futures_lite::io::{self, BufReader, BufWriter};

let input: &[u8] = b"hello";
let reader = BufReader::new(input);

let mut output = Vec::new();
let writer = BufWriter::new(&mut output);

io::copy(reader, writer).await?;