<s>
is	O
a	O
POSIX	O
system	O
call	O
to	O
wait	O
for	O
one	O
or	O
more	O
file	B-Application
descriptors	I-Application
to	O
become	O
ready	O
for	O
use	O
.	O
</s>
<s>
On	O
*	O
BSD	B-Operating_System
and	O
macOS	B-Application
,	O
it	O
has	O
been	O
largely	O
superseded	O
by	O
kqueue	B-Application
in	O
high	O
performance	O
applications	O
.	O
</s>
<s>
On	O
Linux	B-Operating_System
,	O
it	O
has	O
been	O
superseded	O
by	O
and	O
.	O
</s>
