<s>
imake	B-Application
is	O
a	O
build	B-Application
automation	I-Application
system	I-Application
written	O
for	O
the	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
.	O
</s>
<s>
It	O
was	O
used	O
by	O
X	B-Operating_System
from	O
X11R1	O
(	O
1987	O
)	O
to	O
X11R6.9	O
(	O
2005	O
)	O
,	O
and	O
continued	O
to	O
be	O
used	O
in	O
XFree86	B-Device
(	O
last	O
commit	O
2009	O
)	O
.	O
</s>
<s>
It	O
is	O
implemented	O
on	O
top	O
of	O
the	O
C	B-Language
preprocessor	I-Language
and	O
make	B-Application
.	O
</s>
<s>
imake	B-Application
generates	O
makefiles	O
from	O
a	O
template	O
,	O
a	O
set	O
of	O
C	B-Language
preprocessor	I-Language
macro	O
functions	O
,	O
and	O
a	O
per-directory	O
input	O
file	O
called	O
an	O
Imakefile	O
.	O
</s>
<s>
This	O
allows	O
machine	O
dependencies	O
(	O
such	O
as	O
compiler	B-Language
options	O
,	O
alternate	O
command	O
names	O
,	O
and	O
special	O
make	B-Application
rules	O
)	O
to	O
be	O
kept	O
separate	O
from	O
the	O
descriptions	O
of	O
the	O
various	O
items	O
to	O
be	O
built	O
.	O
</s>
<s>
imake	B-Application
was	O
heavily	O
used	O
for	O
X	B-Operating_System
and	O
X-related	O
software	O
through	O
the	O
1990s	O
,	O
and	O
for	O
unrelated	O
software	O
such	O
as	O
ChorusOS	B-Operating_System
.	O
</s>
<s>
It	O
was	O
also	O
used	O
for	O
configuration	B-General_Concept
management	I-General_Concept
.	O
</s>
<s>
With	O
the	O
release	O
of	O
X.org	B-Operating_System
X11R7.0	I-Operating_System
,	O
it	O
was	O
replaced	O
by	O
GNU	B-Application
Autotools	I-Application
.	O
</s>
<s>
(	O
X11R6.9	O
and	O
X11R7.0	O
were	O
the	O
same	O
codebase	O
with	O
a	O
different	O
build	B-Application
system	I-Application
.	O
)	O
.	O
</s>
<s>
X.Org	O
plans	O
to	O
use	O
Meson	B-Application
in	O
the	O
future	O
instead	O
of	O
Autotools	B-Application
.	O
</s>
