The LINKAGE TYPE clause specifies the type of linkage to be made on a CALL
to or a CANCEL of the program specified by literal-7, and to the type of linkage
to be made on the SET statement.

LINKAGE TYPE Clause - Format
(1)
>>-LINKAGE------+------+--+----+--+-environment-name-3-+--FOR--->
'-TYPE-' '-IS-' +-PROGRAM------------+
'-PROCEDURE----------'
.---------------------------------------------.
V |
>----literal-7--+------------------------------+-+-------------><
'-USING--| linkage-arguments |-'
linkage-arguments
.-------------------------------------------------------------------.
V |
|----+-ALL---------------------------------------+--+-----+--DESCRIBED-+--|
| .---------------------------------------. | +-IS--+
| V | | '-ARE-'
'---integer-1--+------------------------+-+-'
'-+-THRU----+--integer-2-'
'-THROUGH-'
Notes:
- IBM® Extension
- environment-name-3
- Environment-name-3 can be defined as:
- PGM
- Linkage to a program object (*PGM) is generated.
- PRC
- Linkage to an ILE procedure is generated.
- SYS
- Linkage to a system-supplied procedure is generated.
- PROGRAM
- Linkage to a program object (*PGM) is generated. This is synonymous
to an environment-name-3 of PGM.
- PROCEDURE
- Linkage to an ILE procedure is generated. This is synonymous to an environment-name-3
of PRC.
- literal-7
- Literal-7 is the name of the program object or procedure. Literal-7
can contain an extended-name. It can be at most 10 characters long for program
names and 256 characters long for procedure names. Literal-7 is affected by
the OPTION(*MONOPRC) parameter. When *MONOPROC is specified, lowercase characters
are converted to uppercase and the rules for formation of a program-name are
followed. See program-name in PROGRAM-ID Paragraph for
details.
- USING
- Specifies which parameters are to have their operational descriptors
made available to the called procedure. These parameters must be defined as
elementary data items with a USAGE of DISPLAY or DISPLAY-1. They may not be
reference modified.
The USING clause is allowed for a linkage type of procedure
and applies only to a CALL statement.
- integer-1, integer-2
- Must be a positive non-zero integer. Specifies the ordinal position
of any parameter described using operational descriptors.
Integer-2 must
be greater than integer-1.
- DESCRIBED
- The parameters specified by integer-1 through integer-2 are passed along
with corresponding operational descriptors. If ALL is specified, all parameters
defined for the procedure are passed along with corresponding operational
descriptors, where applicable.