<s>
GNU	B-Application
cflow	I-Application
is	O
a	O
flow	B-Application
graph	I-Application
generator	I-Application
that	O
is	O
part	O
of	O
the	B-Application
GNU	I-Application
Project	I-Application
.	O
</s>
<s>
It	O
reads	O
a	O
collection	O
of	O
C	B-Language
source	O
files	O
and	O
generates	O
a	O
C	B-Language
flow	O
graph	O
of	O
external	O
references	O
.	O
</s>
<s>
It	O
was	O
initially	O
an	O
implementation	O
of	O
the	O
UNIX	B-Application
utility	I-Application
cflow	O
.	O
</s>
<s>
cflow	O
is	O
a	O
Unix	B-Application
command	I-Application
generating	O
a	O
C-language	O
flowgraph	O
.	O
</s>
<s>
Besides	O
GNU	O
,	O
there	O
are	O
other	O
implementations	O
of	O
cflow	O
,	O
like	O
the	O
one	O
for	O
Tru64	B-Operating_System
Unix	I-Operating_System
.	O
</s>
