pub trait WriteExt: Write {
fn write<'a>(&'a mut self, buf: &'a [u8]) -> WriteFuture<'a, Self>
where
Self: Unpin,
{ ... }
fn flush(&mut self) -> FlushFuture<'_, Self>
where
Self: Unpin,
{ ... }
fn write_vectored<'a>(
&'a mut self,
bufs: &'a [IoSlice<'a>]
) -> WriteVectoredFuture<'a, Self>
where
Self: Unpin,
{ ... }
fn write_all<'a>(&'a mut self, buf: &'a [u8]) -> WriteAllFuture<'a, Self>
where
Self: Unpin,
{ ... }
fn write_fmt<'a>(
&'a mut self,
fmt: Arguments<'_>
) -> WriteFmtFuture<'a, Self>
where
Self: Unpin,
{ ... }
}Expand description
Extension methods for Write.
Provided methods
Writes some bytes into the byte stream.
Returns the number of bytes written from the start of the buffer.
If the return value is Ok(n) then it must be guaranteed that
0 <= n <= buf.len(). A return value of 0 typically means that the underlying
object is no longer able to accept bytes and will likely not be able to in the
future as well, or that the buffer provided is empty.
Examples
use async_std::fs::File;
use async_std::prelude::*;
let mut file = File::create("a.txt").await?;
let n = file.write(b"hello world").await?;Flushes the stream to ensure that all buffered contents reach their destination.
Examples
use async_std::fs::File;
use async_std::prelude::*;
let mut file = File::create("a.txt").await?;
file.write_all(b"hello world").await?;
file.flush().await?;Like write, except that it writes from a slice of buffers.
Data is copied from each buffer in order, with the final buffer read from possibly
being only partially consumed. This method must behave as a call to write with
the buffers concatenated would.
The default implementation calls write with either the first nonempty buffer
provided, or an empty one if none exists.
Writes an entire buffer into the byte stream.
This method will continuously call write until there is no more data to be
written or an error is returned. This method will not return until the entire
buffer has been successfully written or such an error occurs.
Examples
use async_std::fs::File;
use async_std::prelude::*;
let mut file = File::create("a.txt").await?;
file.write_all(b"hello world").await?;Writes a formatted string into this writer, returning any error encountered.
This method will continuously call write until there is no more data to be
written or an error is returned. This future will not resolve until the entire
buffer has been successfully written or such an error occurs.
Examples
use async_std::io::prelude::*;
use async_std::fs::File;
let mut buffer = File::create("foo.txt").await?;
// this call
write!(buffer, "{:.*}", 2, 1.234567).await?;
// turns into this:
buffer.write_fmt(format_args!("{:.*}", 2, 1.234567)).await?;