Struct wasmtime_wasi::preview2::pipe::WritePipe

pub struct WritePipe<W: Write> { /* private fields */ }

A virtual pipe write end.

use wasmtime_wasi::preview2::{pipe::WritePipe, WasiCtxBuilder, Table};
let mut table = Table::new();
let stdout = WritePipe::new_in_memory();
let mut ctx = WasiCtxBuilder::new().set_stdout(stdout.clone()).build(&mut table).unwrap();
// use ctx and table in an instance, then make sure it is dropped:
drop(ctx);
drop(table);
let contents: Vec<u8> = stdout.try_into_inner().expect("sole remaining reference to WritePipe").into_inner();
println!("contents of stdout: {:?}", contents);

Implementations

impl<W: Write> WritePipe<W>

pub fn new(w: W) -> Self

Create a new pipe from a Write type.

All Handle write operations delegate to writing to this underlying writer.

pub fn from_shared(writer: Arc<RwLock<W>>) -> Self

Create a new pipe from a shareable Write type.

All Handle write operations delegate to writing to this underlying writer.

pub fn try_into_inner(self) -> Result<W, Self>

Try to convert this WritePipe<W> back to the underlying W type.

This will fail with Err(self) if multiple references to the underlying W exist.

impl WritePipe<Cursor<Vec<u8>>>

pub fn new_in_memory() -> Self

Create a new writable virtual pipe backed by a Vec<u8> buffer.

Trait Implementations

impl<W: Write> Clone for WritePipe<W>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<W: Debug + Write> Debug for WritePipe<W>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<W: Write + Any + Send + Sync> OutputStream for WritePipe<W>

fn as_any(&self) -> &dyn Any

fn write<'life0, 'life1, 'async_trait>( &'life0 mut self, buf: &'life1 [u8] ) -> Pin<Box<dyn Future<Output = Result<u64, Error>> + Send + 'async_trait>>where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Write bytes. On success, returns the number of bytes written.

fn write_zeroes<'life0, 'async_trait>( &'life0 mut self, nelem: u64 ) -> Pin<Box<dyn Future<Output = Result<u64, Error>> + Send + 'async_trait>>where Self: 'async_trait, 'life0: 'async_trait,

Repeatedly write a byte to a stream.

fn writable<'life0, 'async_trait>( &'life0 self ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>where Self: 'async_trait, 'life0: 'async_trait,

Test whether this stream is writable.

fn pollable_write(&self) -> Option<BorrowedFd<'_>>

If this stream is writing from a host file descriptor, return it so that it can be polled with a host poll.

fn write_vectored<'a, 'life0, 'life1, 'async_trait>( &'life0 mut self, _bufs: &'life1 [IoSlice<'a>] ) -> Pin<Box<dyn Future<Output = Result<u64, Error>> + Send + 'async_trait>>where Self: 'async_trait, 'a: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Vectored-I/O form of write.

fn is_write_vectored(&self) -> bool

Test whether vectored I/O writes are known to be optimized in the underlying implementation.

fn splice<'life0, 'life1, 'async_trait>( &'life0 mut self, src: &'life1 mut dyn InputStream, nelem: u64 ) -> Pin<Box<dyn Future<Output = Result<(u64, bool), Error>> + Send + 'async_trait>>where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Transfer bytes directly from an input stream to an output stream.