<s>
The	O
script	O
command	O
is	O
a	O
Unix	B-Application
utility	I-Application
that	O
records	O
a	O
terminal	B-General_Concept
session	O
.	O
</s>
<s>
It	O
dates	O
back	O
to	O
the	O
1979	O
3.0	O
BSD	B-Operating_System
.	O
</s>
<s>
It	O
uses	O
a	O
pseudoterminal	B-Protocol
for	O
this	O
purpose	O
,	O
so	O
programs	O
act	O
exactly	O
as	O
if	O
they	O
were	O
on	O
a	O
terminal	B-General_Concept
.	O
</s>
<s>
The	O
util-linux	B-Application
command	O
offers	O
a	O
replay	O
function	O
to	O
its	O
script	O
,	O
which	O
supports	O
using	O
an	O
extra	O
timing	O
file	O
for	O
character-level	O
information	O
.	O
</s>
<s>
The	O
Unix	B-Application
operating	I-Application
systems	I-Application
make	O
this	O
possible	O
by	O
use	O
of	O
pipes	B-Operating_System
and	O
redirects	O
.	O
</s>
<s>
All	O
shells	O
related	O
to	O
Bourne	B-Device
shell	I-Device
(	O
namely	O
:	O
sh	B-Application
,	O
bash	B-Operating_System
,	O
and	O
ksh	B-Language
)	O
allow	O
the	O
stdout	O
and	O
stderr	O
to	O
be	O
attached	O
to	O
a	O
named	B-Operating_System
pipe	I-Operating_System
and	O
redirected	O
to	O
the	O
tee	O
command	O
.	O
</s>
<s>
However	O
,	O
some	O
interactive	O
programs	O
(	O
such	O
as	O
python	B-Language
)	O
do	O
not	O
echo	O
their	O
standard	O
input	O
when	O
run	O
under	O
the	O
resulting	O
shell	O
,	O
although	O
they	O
do	O
when	O
run	O
under	O
the	O
script	O
command	O
,	O
again	O
due	O
to	O
the	O
detection	O
of	O
a	O
terminal	B-General_Concept
.	O
</s>
<s>
The	O
ttyrec	B-Device
program	O
from	O
2000	O
provides	O
the	O
same	O
kind	O
of	O
functionality	O
and	O
offers	O
several	O
bindings	O
.	O
</s>
<s>
The	O
timing	O
is	O
similar	O
to	O
util-linux	B-Application
.	O
</s>
<s>
A	O
more	O
modern	O
take	O
on	O
the	O
concept	O
is	O
"	O
asciicast	O
"	O
JSON	B-General_Concept
,	O
used	O
by	O
asciinema	O
.	O
</s>
