Crate serialport_stream 

Async serial port I/O as AsyncRead and AsyncWrite, with optional Stream support.

Async runtime agnostic: this crate implements futures traits only and does not depend on Tokio, async-std, or any other executor. Use it with any runtime that polls those futures (Tokio, async-std, futures_lite::future::block_on, etc.).

Configure and open ports with new → SerialPortStreamBuilder → .open(). Line settings, DTR, and buffer clearing are applied at open time.

Features

• stream (optional): Stream, TryStreamExt, and SerialPortStream::try_poll_next. Starts a background receive pump into an in-memory FIFO (poll-based thread on Unix, WaitCommEvent thread on Windows). With stream enabled, AsyncRead and Stream share that FIFO.
• tracing (optional): diagnostic logs.

Read paths

Platform	AsyncRead (no stream)	AsyncRead + Stream (stream feature)
Unix	Direct async-io poll on the port fd	Shared poll-based background thread → FIFO
Windows	Overlapped ReadFile + windows thread-pool	Shared background read thread → FIFO

When stream is enabled, AsyncRead and Stream share the same background receive FIFO (Unix and Windows).

Write path

On Unix, AsyncWrite uses async-io. On Windows, overlapped WriteFile with a windows thread-pool completion.

AsyncReadExt and AsyncWriteExt are re-exported from futures.

use serialport_stream::{new, AsyncReadExt, AsyncWriteExt};

let mut stream = new("/dev/ttyUSB0", 115200).open()?;
stream.write_all(b"PING\r\n").await?;
let mut buf = [0u8; 256];
let n = stream.read(&mut buf).await?;

Modules

line_settings

Structs

SerialPortStream

An opened serial port for async reads and writes.

SerialPortStreamBuilder

Builder for serial port path, line settings, and one-shot open options.

Enums

ClearBuffer

Buffer(s) to clear.

DataBits

Number of data bits per character.

FlowControl

Flow control mode.

Parity

Parity checking mode.

StopBits

Number of stop bits.

Traits

AsyncRead

Read bytes asynchronously.

AsyncReadExt

An extension trait which adds utility methods to AsyncRead types.

AsyncWrite

Write bytes asynchronously.

AsyncWriteExt

An extension trait which adds utility methods to AsyncWrite types.

Stream

A stream of values produced asynchronously.

TryStreamExt

Adapters specific to Result-returning streams

Functions

new

Creates a SerialPortStreamBuilder with default line settings (8N1, no flow control).