<s>
In	O
Unix	B-Application
and	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
,	O
printf	B-Language
(	O
"	O
print	O
formatted	O
"	O
)	O
is	O
a	O
shell	B-Operating_System
builtin	O
(	O
and	O
utility	O
program	B-Application
)	O
that	O
formats	O
and	O
prints	O
data	O
.	O
</s>
<s>
The	O
command	B-Application
accepts	O
a	O
printf	B-Language
format	I-Language
string	I-Language
,	O
which	O
specifies	O
methods	O
for	O
formatting	O
items	O
,	O
and	O
a	O
list	O
of	O
items	O
to	O
be	O
formatted	O
.	O
</s>
<s>
Characters	O
in	O
the	O
format	B-Language
string	I-Language
are	O
copied	O
to	O
the	O
output	O
or	O
,	O
if	O
a	O
%	O
is	O
encountered	O
,	O
are	O
used	O
to	O
format	O
an	O
item	O
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
standard	O
formats	O
,	O
%b	O
causes	O
printf	B-Language
to	O
expand	O
backslash	O
escape	O
sequences	O
(	O
for	O
example	O
\n	O
for	O
newline	O
)	O
,	O
and	O
%q	O
outputs	O
an	O
item	O
that	O
can	O
be	O
used	O
as	O
shell	B-Operating_System
input	O
.	O
</s>
<s>
The	O
format	B-Language
string	I-Language
is	O
reused	O
if	O
there	O
are	O
more	O
items	O
than	O
format	O
specs	O
.	O
</s>
<s>
It	O
was	O
inherited	O
into	O
the	O
first	O
version	O
of	O
POSIX.1	O
and	O
the	O
Single	O
Unix	B-Application
Specification	O
.	O
</s>
<s>
It	O
first	O
appeared	O
in	O
4.3BSD-Reno	B-Operating_System
.	O
</s>
<s>
The	O
version	O
of	O
printf	B-Language
bundled	O
in	O
GNU	B-Application
coreutils	I-Application
was	O
written	O
by	O
David	O
MacKenzie	O
.	O
</s>
<s>
It	O
has	O
an	O
extension	O
for	O
escaping	O
strings	O
in	O
POSIX-shell	O
format	O
.	O
</s>
