sndio home

About - what is sndio?

Sndio is a small audio and MIDI framework part of the OpenBSD project and ported to FreeBSD, Linux and NetBSD. It provides a lightweight audio & MIDI server and a fully documented user-space API to access either the server or directly the hardware in a uniform way. Sndio is designed to work for desktop applications, but pays special attention to synchronization mechanisms and reliability required by music applications. Reliability through simplicity are part of the project goals.

Operating systems supporting sndio

This source code builds on any OpenBSD or Linux system with no modifications. Patches to make sndio build on FreeBSD and NetBSD are available in their respective ports trees and are being integrated in this distribution.

Binaries are available for the following operating systems:

Porting sndio, consists in writing a module for the sndio library; it's around a thousand of lines of C. The sndio daemon itself uses this library for audio I/O so it requires virtually no porting efforts.

Programs supporting sndio

Many open-source programs including major media-players, web-browsers, audio libraries and utilities have native sndio support. Other programs have patches in the OpenBSD ports tree waiting for upstream integration.

Downloads & installation

Refer to installation instructions for more details.

Source tar-balls:

Using CVS:

cvs -d checkout -P sndio


The complete documentation is part of the OpenBSD project:

A mailing-list dedicated to non-OpenBSD-related discussions is available (archives are here).


Related projects

Copyright (c) 2013 Alexandre Ratchov
Last updated jan 8, 2016