Identifying a procedure in SYS1.PROCLIB

The procedure in SYS1.PROCLIB specifies the first program to run in the new address space after the optional initialization routine. You can specify the name of this procedure either on the ASNAME or STPARM parameter.

On the ASNAME parameter, you specify the name of the new address space, which must be the same as the name of the procedure in SYS1.PROCLIB. (This parameter assumes that you have the procedure in SYS1.PROCLIB.) You cannot pass parameters to JCL through ASNAME.
On the STPARM parameter, you specify the address of a parameter string that consists of a two-byte length field followed by up to 124 bytes of parameter data. The length field identifies the length of the parameter data (not including the length field itself). The parameter data begins with the name of the new address space, which must be the same as the name of the procedure in SYS1.PROCLIB. The name is followed by parameters. You can pass parameters to JCL through STPARM.

If you do not need special DD statements for data sets, you can use the common system address space procedure IEESYSAS. In the parameter data specified by the STPARM parameter, specify IEESYSAS and the name of the first program to run in the address space. The format of the parameter data is as follows:

IEESYSAS.x,PROG=y

where:

x: The name of the address space
y: The name of the first program that executes in the new address space

Through IEESYSAS, you name the address space x and generate an EXEC statement with PGM=y.

Example of a parameter string

To request that the system create the RMA address space and identify FIRSTPGM as the first program to execute in the new address space, code the following:

ASCRE STPARM=STRMA,...

where STRMA is the address of the parameter string.

The parameter string is coded as follows:

STRMA  DS    0H
       DC    H'26'
       DC    CL26'IEESYSAS.RMA,PROG=FIRSTPGM'

where:

H'26': Indicates that the parameter string is 26 characters long
IEESYSAS: Identifies the procedure to be used
RMA: The name of the new address space
FIRSTPGM: The name of the first program in the new address space

If you have data sets that need DD statements, you will have to write your own procedure in SYS1.PROCLIB. Identify the procedure through the parameter string that the STPARM parameter points to. The parameter string starts with a halfword field that tells the length of the parameter string. It is followed by parameter data.