<s>
sndio	B-Application
is	O
the	O
software	O
layer	O
of	O
the	O
OpenBSD	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
that	O
manages	O
sound	B-Device
cards	I-Device
and	O
MIDI	O
ports	O
.	O
</s>
<s>
It	O
provides	O
an	O
optional	O
sound	B-Application
server	I-Application
and	O
a	O
documented	O
application	B-Application
programming	I-Application
interface	I-Application
to	O
access	O
either	O
the	O
server	O
or	O
the	O
audio	O
and	O
MIDI	O
hardware	O
in	O
a	O
uniform	O
way	O
.	O
</s>
<s>
sndio	B-Application
is	O
designed	O
to	O
work	O
for	O
desktop	O
applications	O
,	O
but	O
pays	O
special	O
attention	O
to	O
synchronization	O
mechanisms	O
and	O
reliability	O
required	O
by	O
music	O
applications	O
.	O
</s>
<s>
The	O
audio	O
and	O
MIDI	O
server	O
is	O
the	O
main	O
component	O
of	O
sndio	B-Application
.	O
</s>
<s>
It	O
aims	O
to	O
fill	O
the	O
gap	O
between	O
programs	O
requirements	O
and	O
the	O
bare	O
hardware	O
as	O
exposed	O
by	O
operating	B-General_Concept
system	I-General_Concept
device	O
drivers	O
.	O
</s>
<s>
route	O
audio	O
and	O
MIDI	O
data	O
through	O
the	O
network	O
;	O
this	O
allows	O
programs	O
running	O
on	O
one	O
computer	O
to	O
use	O
the	O
sound	B-Device
card	I-Device
of	O
another	O
computer	O
.	O
</s>
<s>
expose	O
the	O
sound	B-Device
card	I-Device
clock	O
as	O
MIDI	O
timecode	O
(	O
MTC	O
)	O
,	O
allowing	O
MIDI	O
programs	O
(	O
e.g.	O
</s>
<s>
The	O
last	O
few	O
points	O
are	O
hooks	O
in	O
the	O
sound	B-Application
server	I-Application
aiming	O
to	O
improve	O
interoperability	O
between	O
audio	O
and	O
MIDI	O
programs	O
.	O
</s>
<s>
Minimal	O
server	O
capabilities	O
were	O
added	O
to	O
—	O
an	O
audio	O
stream	O
manipulation	O
tool	O
and	O
predecessor	O
to	O
—	O
in	O
October	O
2008	O
,	O
shipping	O
with	O
OpenBSD	B-Operating_System
4.5	O
.	O
</s>
<s>
In	O
December	O
2011	O
,	O
was	O
renamed	O
to	O
and	O
later	O
shipped	O
with	O
OpenBSD	B-Operating_System
5.1	O
as	O
the	O
default	O
sound	B-Application
server	I-Application
started	O
at	O
operating	B-General_Concept
system	I-General_Concept
boot	O
.	O
</s>
