<s>
XDarwin	B-Device
is	O
an	O
obsolete	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
(	O
X11	B-Operating_System
)	O
display	O
server	O
for	O
the	O
Darwin	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
and	O
early	O
versions	O
of	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
.	O
XDarwin	B-Device
allows	O
one	O
to	O
use	O
programs	O
written	O
for	O
X11	B-Operating_System
on	O
those	O
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
XDarwin	B-Device
was	O
ported	O
by	O
the	O
XonX	B-Device
project	O
,	O
an	O
offshoot	O
project	O
created	O
by	O
XFree86	B-Device
developers	O
.	O
</s>
<s>
It	O
is	O
integrated	O
in	O
the	O
upstream	O
source	O
code	O
of	O
the	O
XFree86	B-Device
and	O
Xorg	B-Operating_System
servers	I-Operating_System
,	O
where	O
it	O
is	O
maintained	O
.	O
</s>
<s>
Originally	O
,	O
XDarwin	B-Device
required	O
an	O
X	B-Operating_System
window	I-Operating_System
manager	O
to	O
run	O
.	O
</s>
<s>
For	O
this	O
task	O
,	O
a	O
window	O
manager	O
called	O
OroborOSX	O
was	O
created	O
;	O
this	O
was	O
based	O
on	O
Oroborus	O
,	O
another	O
X	B-Operating_System
window	I-Operating_System
manager	O
,	O
but	O
modified	O
to	O
look	O
like	O
the	O
native	O
Mac	O
OS	O
window	O
manager	O
.	O
</s>
<s>
More	O
recent	O
versions	O
of	O
XDarwin	B-Device
can	O
also	O
run	O
in	O
rootless	O
mode	O
,	O
which	O
is	O
to	O
say	O
that	O
it	O
integrates	O
with	O
the	O
native	O
window	O
manager	O
instead	O
of	O
requiring	O
such	O
a	O
program	O
specifically	O
for	O
X	B-Operating_System
.	O
</s>
<s>
Before	O
the	O
introduction	O
of	O
Apple	O
's	O
X11.app	B-Operating_System
,	O
XDarwin	B-Device
was	O
the	O
only	O
X11	B-Operating_System
server	I-Operating_System
available	O
for	O
OS	B-Operating_System
X	I-Operating_System
.	O
</s>
<s>
According	O
to	O
the	O
XonX	B-Device
project	O
,	O
X11.app	B-Operating_System
itself	O
contains	O
code	O
from	O
XDarwin	B-Device
.	O
</s>
<s>
Programs	O
such	O
as	O
OpenOffice.org	B-Application
use	O
XDarwin	B-Device
to	O
run	O
in	O
the	O
X11	B-Operating_System
windowing	O
environment	O
,	O
either	O
in	O
a	O
rootless	O
or	O
full-screen	O
mode	O
.	O
</s>
<s>
A	O
version	O
of	O
the	O
program	O
was	O
created	O
for	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
Panther	I-Operating_System
or	O
higher	O
that	O
runs	O
in	O
the	O
native	O
Aqua	B-Application
interface	I-Application
.	O
</s>
