Calling block structure

The parameter structure outlined below is shown in block form in Figure 1.

ADRDSSU

The name of the DFSMSdss module main entry point.

OPTPTR

The pointer to the option list and similar to OPTIONADDR described in z/OS DFSMSdfp Utilities. This parameter lets you specify processing options and must be specified even if the list is a null list. If you do not want to specify any parameters to DFSMSdss, this pointer must point to a halfword of binary zeros.

You can invoke DFSMSdss using the standard application interface. This API allows you to specify in the options list those values that you can specify in the EXEC PARM field when you invoke DFSMSdss using JCL. You can also invoke DFSMSdss using the cross memory application interface. The values that you can specify in the options list include those values that can be specified in the EXEC PARM field when invoking DFSMSdss with JCL. Additionally, you can specify values that are specific to the cross memory application interface. For a list of the values that can be specified in the EXEC PARM field when invoking DFSMSdss with JCL, see How to control DFSMSdss through PARM information in the EXEC statement. For a list of the values that are specific to the cross memory application interface, see Using the cross memory application interface to control DFSMSdss.

The first field, called the option-list length field, is a halfword field specifying the length of the list (excluding the field itself) as a binary value. If you do not want to specify any options, set the option-list length field to binary zeros. In your JCL for the calling program, if you code parameters (PARM=value) on the EXEC statement, DFSMSdss does not recognize them unless OPTPTR points to them.

The options must comply with the parameter syntax of the DFSMSdss EXEC parameter values. If you do not want to specify subsequent parameters, you can omit them from the list.

DDPTR

The pointer to the DDNAME list and similar to DDNAMEADDR described in z/OS DFSMSdfp Utilities. The DDNAME list provides a way to specify alternate names for the SYSIN and SYSPRINT data sets. The DDNAME list is a variable length field made up of a halfword field followed by unseparated 8-character, left-justified (right padded with blanks) fields. Each 8-character field is reserved for a specific DDNAME. DFSMSdss uses only two of these fields: SYSIN and SYSPRINT. The other fields are provided as a standard implementation consistent with existing system utility invocation procedures, must be filled with binary zeros, and are ignored by DFSMSdss.

The first field, called the DDNAME-list length field, is a halfword field specifying the length of the list (excluding the field itself) as a binary value for the number 48.

If you do not want to specify an alternate DDNAME for the SYSIN or SYSPRINT data sets, set the DDNAME-list length field to the correct length and set all of the 8-character fields to binary zeros.

If you want to specify an alternate DDNAME for the SYSIN data set, specify this parameter and enter the alternate DDNAME in the fifth 8-character field. Otherwise, enter all binary zeros in the field.

If you want to specify an alternate DDNAME for the SYSPRINT data set, specify this parameter and enter the alternate DDNAME in the sixth 8-character field. Otherwise, enter all binary zeros in the field.

If you do not want to specify subsequent parameters, you can omit them from the list.

PAGEPTR

The pointer to the page-number list and similar to HDINGADDR described in z/OS DFSMSdfp Utilities. This list provides a way to specify the starting page number for system output on the SYSPRINT data set. The page-number list is a fixed-length 6-byte field made up of a halfword field followed by a 4-byte EBCDIC page count, which specifies the starting page number for DFSMSdss to use for the SYSPRINT data set. If a value is specified both here and in the OPTPTR list, this value is used, and the OPTPTR value is ignored.

The first field, called the page-number-list length field, is a halfword field specifying the length of the list (excluding the field itself) as a binary value. The length is usually 4.

If you do not want to specify a starting page number, set the page-number-list length field to binary zeros. If you want to specify a starting page number, you must specify this parameter and a 4-character page value. If the page number is specified (page-number-list length field is not binary zeros), DFSMSdss resets this field to the current page number upon completion of the present invocation. If the page number is not specified, this field is not changed by DFSMSdss.

If you do not want to specify subsequent parameters, you can omit them from the list.

UIMPTR

The pointer to the user interaction module (UIM) list. There is no comparable parameter described in z/OS DFSMSdfp Utilities. This parameter provides a way to specify the name or address of a vector-implemented exit module that is to interact with DFSMSdss for the various I/O and data set operations. The UIM list is of variable length and consists of a halfword field followed by a 4-byte address or 8-character left-justified (padded on the right with blanks) string field that specifies the address of the UIM entry point or the load module name (located through the normal LINKLIB structure) of the UIM. If you do not want to specify a UIM, do not specify this parameter.

The first field, called the UIM-list length field, is a halfword field specifying the length of the list (excluding the field itself) as a binary value. If you do not want to specify an option, set the option-list length field to binary zeros. If the address of the UIM is being passed, it specifies the length as 4, or as 8 if the name of the UIM is being passed.

If you want to specify a UIM, you must specify the name or address of the UIM in the field following the UIM-list length field. See System programming information for more details on the use of this module.

UAPTR

The pointer to the user-area list. There is no comparable parameter in z/OS DFSMSdfp Utilities. This parameter provides a way to specify the address of an area to be passed to the UIM at each DFSMSdss exit point. The user-area list is of fixed length, consisting of a halfword field called the user-area-list length field, and a single 4-byte address that locates the user area starting address.

If you use the user area, the length must be set to 4 and the address of the user area must be specified in a second field.

ASIDPTR

The pointer to the address-space-identifier list. There is no comparable parameter described in z/OS DFSMSdfp Utilities. This optional parameter, which is applicable only when you use ADRXMAIA instead of ADRDSSU, lets you specify an identifier for the address space that ADRXMAIA uses for the DFSMSdss program. The address-space-identifier list is of fixed length, consisting of a halfword field and a single 8-byte character field. The default value, if not set by the application program, is "DFSMSDSS." This value is set to "DSSBATCH" when JCL is used to invoke ADRXMAIA, but can be specified through the ASPACE=name PARM field.

ADRXMAIA automatically creates the address space as needed. The identified address space can also be created by the operator START command by specifying an appropriately named PROCLIB member name.

PARAM

On the ATTACH and LINK macros, the keyword with which you specify the names of the pointers that are passed to DFSMSdss

VL

Indicates that the list is variable length. Both the ATTACH and LINK macros require specifying VL=1.

Figure 1. DFSMSdss Application Interface Structure