1.0.0[−][src]Module std::sync::mpsc
Multi-producer, single-consumer FIFO queue communication primitives.
This module provides message-based communication over channels, concretely defined among three types:
A Sender
or SyncSender
is used to send data to a Receiver
. Both
senders are clone-able (multi-producer) such that many threads can send
simultaneously to one receiver (single-consumer).
These channels come in two flavors:
-
An asynchronous, infinitely buffered channel. The
channel
function will return a(Sender, Receiver)
tuple where all sends will be asynchronous (they never block). The channel conceptually has an infinite buffer. -
A synchronous, bounded channel. The
sync_channel
function will return a(SyncSender, Receiver)
tuple where the storage for pending messages is a pre-allocated buffer of a fixed size. All sends will be synchronous by blocking until there is buffer space available. Note that a bound of 0 is allowed, causing the channel to become a "rendezvous" channel where each sender atomically hands off a message to a receiver.
Disconnection
The send and receive operations on channels will all return a Result
indicating whether the operation succeeded or not. An unsuccessful operation
is normally indicative of the other half of a channel having "hung up" by
being dropped in its corresponding thread.
Once half of a channel has been deallocated, most operations can no longer
continue to make progress, so Err
will be returned. Many applications
will continue to unwrap
the results returned from this module,
instigating a propagation of failure among threads if one unexpectedly dies.
Examples
Simple usage:
use std::thread; use std::sync::mpsc::channel; // Create a simple streaming channel let (tx, rx) = channel(); thread::spawn(move|| { tx.send(10).unwrap(); }); assert_eq!(rx.recv().unwrap(), 10);Run
Shared usage:
use std::thread; use std::sync::mpsc::channel; // Create a shared channel that can be sent along from many threads // where tx is the sending half (tx for transmission), and rx is the receiving // half (rx for receiving). let (tx, rx) = channel(); for i in 0..10 { let tx = tx.clone(); thread::spawn(move|| { tx.send(i).unwrap(); }); } for _ in 0..10 { let j = rx.recv().unwrap(); assert!(0 <= j && j < 10); }Run
Propagating panics:
use std::sync::mpsc::channel; // The call to recv() will return an error because the channel has already // hung up (or been deallocated) let (tx, rx) = channel::<i32>(); drop(tx); assert!(rx.recv().is_err());Run
Synchronous channels:
use std::thread; use std::sync::mpsc::sync_channel; let (tx, rx) = sync_channel::<i32>(0); thread::spawn(move|| { // This will wait for the parent thread to start receiving tx.send(53).unwrap(); }); rx.recv().unwrap();Run
Structs
IntoIter | An owning iterator over messages on a |
Iter | |
Receiver | The receiving half of Rust's |
RecvError | |
SendError | An error returned from the |
Sender | The sending-half of Rust's asynchronous |
SyncSender | The sending-half of Rust's synchronous |
TryIter | An iterator that attempts to yield all pending values for a |
Enums
RecvTimeoutError | This enumeration is the list of possible errors that made |
TryRecvError | This enumeration is the list of the possible reasons that |
TrySendError | This enumeration is the list of the possible error outcomes for the
|
Functions
channel | Creates a new asynchronous channel, returning the sender/receiver halves.
All data sent on the |
sync_channel | Creates a new synchronous, bounded channel.
All data sent on the |