<s>
Data	O
Language	O
One	O
(	O
Data	O
Language/I	O
,	O
DL/I	B-Language
,	O
Data	O
Language/One	O
,	O
Data	O
Language/One	O
)	O
is	O
the	O
language	O
system	O
used	O
to	O
access	O
IBM	O
's	O
IMS	B-Application
databases	O
and	O
its	O
data	O
communication	O
system	O
.	O
</s>
<s>
calling	O
CBLTDLI	O
from	O
a	O
COBOL	B-Application
program	O
.	O
</s>
<s>
This	O
stub	O
is	O
linked	O
to	O
the	O
calling	O
program	O
,	O
passes	O
on	O
the	O
request	O
to	O
the	O
IMS	B-Application
system	I-Application
,	O
and	O
returns	O
the	O
results	O
and	O
a	O
status	O
code	O
.	O
</s>
<s>
In	O
any	O
full-function	O
IMS	B-Application
database	O
,	O
the	O
smallest	O
element	O
that	O
can	O
be	O
retrieved	O
is	O
a	O
segment	O
.	O
</s>
<s>
Other	O
types	O
of	O
PCB	O
are	O
used	O
to	O
send	O
and	O
receive	O
transaction	B-General_Concept
processing	I-General_Concept
messages	O
,	O
access	O
and	O
write	O
to	O
the	O
user	O
’s	O
VDU	B-Device
screen	O
,	O
and	O
to	O
print	O
reports	O
etc	O
.	O
</s>
<s>
For	O
all	O
languages	O
except	O
PL/I	B-Language
,	O
the	O
first	O
parameter	O
in	O
a	O
call	O
is	O
the	O
Function	O
Code	O
a	O
four	O
character	O
field	O
,	O
examples	O
being	O
:	O
“	O
GU	O
”	O
(	O
Get	O
Unique	O
)	O
,	O
“	O
GN	O
”	O
(	O
Get	O
Next	O
)	O
,	O
“	O
REPL	O
”	O
(	O
Replace	O
)	O
,	O
and	O
“	O
ISRT	O
”	O
(	O
Insert	O
)	O
.	O
</s>
<s>
With	O
PL/I	B-Language
,	O
due	O
to	O
the	O
way	O
this	O
language	O
does	O
not	O
mark	O
the	O
last	O
parameter	O
with	O
a	O
'	O
1	O
 '	O
in	O
bit	O
0	O
,	O
the	O
first	O
parameter	O
must	O
instead	O
be	O
a	O
fullword	O
(	O
Fixed	O
Bin(31 )	O
)	O
containing	O
the	O
number	O
of	O
following	O
parameters	O
.	O
</s>
<s>
A	O
typical	O
call	O
from	O
a	O
COBOL	B-Application
program	O
might	O
be	O
.	O
</s>
<s>
A	O
typical	O
call	O
from	O
a	O
PL/I	B-Language
program	O
might	O
be	O
.	O
</s>
