<s>
In	O
computing	O
,	O
a	O
status	B-Device
key	I-Device
is	O
a	O
keyboard	B-Device
key	O
that	O
causes	O
an	O
operating	B-General_Concept
system	I-General_Concept
and/or	O
a	O
program	B-Application
to	O
output	O
status	O
information	O
on	O
a	O
terminal	B-General_Concept
when	O
it	O
is	O
pressed	O
.	O
</s>
<s>
In	O
the	O
event	O
that	O
a	O
program	B-Application
on	O
a	O
terminal	B-General_Concept
produces	O
no	O
indications	O
that	O
it	O
is	O
running	O
,	O
typing	O
the	O
status	B-Device
key	I-Device
will	O
reveal	O
the	O
program	B-Application
's	O
state	O
and	O
activity	O
.	O
</s>
<s>
Older	O
implementations	O
produced	O
only	O
a	O
quick	O
one-line	O
status	O
report	O
for	O
the	O
current	O
job	O
when	O
the	O
status	B-Device
key	I-Device
was	O
pressed	O
.	O
</s>
<s>
Newer	O
implementations	O
support	O
sending	O
a	O
signal	B-Operating_System
to	O
the	O
current	O
process	O
to	O
allow	O
the	O
application	O
to	O
report	O
on	O
status	O
as	O
well	O
.	O
</s>
<s>
Several	O
different	O
operating	B-General_Concept
systems	I-General_Concept
have	O
a	O
status	B-Device
key	I-Device
feature	O
.	O
</s>
<s>
RSTS/E	B-Operating_System
is	O
documented	O
as	O
having	O
a	O
status	B-Device
key	I-Device
at	O
least	O
as	O
far	O
back	O
as	O
1977	O
and	O
it	O
continued	O
to	O
have	O
one	O
into	O
at	O
least	O
the	O
1980s	O
.	O
</s>
<s>
Typing	O
the	O
status	B-Device
key	I-Device
results	O
in	O
output	O
that	O
is	O
represented	O
by	O
the	O
following	O
example	O
:	O
</s>
<s>
On	O
TOPS-10	B-Operating_System
when	O
the	O
CTRL/T	O
(	O
control-T	O
)	O
key	O
is	O
pressed	O
,	O
the	O
monitor	O
prints	O
status	O
information	O
pertaining	O
to	O
the	O
job	O
on	O
the	O
terminal	B-General_Concept
.	O
</s>
<s>
Typing	O
CTRL/T	O
displays	O
a	O
job	O
's	O
progress	O
without	O
interrupting	O
its	B-Application
execution	O
.	O
</s>
<s>
No	O
representation	O
of	O
a	O
control-t	O
character	O
is	O
displayed	O
on	O
the	O
terminal	B-General_Concept
,	O
just	O
the	O
status	O
information	O
.	O
</s>
<s>
TOPS-20	B-Operating_System
reports	O
a	O
shorter	O
list	O
of	O
information	O
than	O
its	B-Application
predecessors	O
:	O
</s>
<s>
ITS	B-Application
copied	O
the	O
idea	O
from	O
TOPS-20	B-Operating_System
,	O
but	O
used	O
the	O
key	O
sequence	O
.	O
</s>
<s>
OpenVMS	B-Operating_System
has	O
a	O
status	B-Device
key	I-Device
which	O
can	O
be	O
customized	O
and	O
works	O
with	O
remote	O
processes	O
.	O
</s>
<s>
4.3BSD-Reno	B-Operating_System
and	O
BSD	B-Operating_System
systems	I-Operating_System
derived	I-Operating_System
from	I-Operating_System
that	I-Operating_System
version	I-Operating_System
and	O
OSF/1	B-Operating_System
have	O
a	O
status	B-Device
key	I-Device
which	O
defaults	O
to	O
Ctrl-T	O
and	O
can	O
be	O
assigned	O
to	O
any	O
key	O
.	O
</s>
<s>
It	O
sends	O
SIGINFO	B-General_Concept
to	O
the	O
current	O
process	O
which	O
is	O
ignored	O
by	O
default	O
but	O
can	O
be	O
configured	O
to	O
call	O
a	O
function	O
which	O
can	O
display	O
status	O
information	O
from	O
the	O
program	B-Application
.	O
</s>
<s>
Because	O
XNU	B-Operating_System
has	O
a	O
FreeBSD	B-Operating_System
kernel	O
which	O
has	O
been	O
modified	O
to	O
be	O
a	O
Mach	O
server	O
process	O
,	O
the	O
terminal	B-General_Concept
driver	O
includes	O
a	O
status	B-Device
key	I-Device
which	O
is	O
inherited	O
.	O
</s>
