An example of mapping a data-in-virtual object to a hiperspace

The following example shows how you would create a non-shared standard hiperspace with a maximum size of one gigabyte and an initial size of 4K bytes. Figure 1 shows the hiperspace with a window that begins at the origin of the hiperspace.

Figure 1. Example of mapping a data-in-virtual object to a hiperspace

This example show an address space and standard hiperspaces with an HSPSERV SREAD and SWRITE happening between them with the hiperspace window offloading to a VSAM linear data set on DASD.

Initially, the window in the hiperspace and the buffer area in the address space are both 4K bytes. (That is, the window takes up the entire initial size of the hiperspace.) The data-in-virtual object is a VSAM linear data set on DASD.

* CREATE A STANDARD HIPERSPACE
  .
  DSPSERV CREATE,TYPE=HIPERSPACE,HSTYPE=SCROLL,NAME=HS1NAME,          X
     STOKEN=HS1STOK,BLOCKS=(ONEGIG,FOURK),ORIGIN=HS1ORG
  .

* MAP THE HIPERSPACE TO THE OBJECT
  .
  DIV     IDENTIFY,ID=OBJID,TYPE=DA,DDNAME=OBJDD
  DIV     ACCESS,ID=OBJID,MODE=UPDATE
  DIV     MAP,ID=OBJID,AREA=HS1ORG,STOKEN=HS1STOK
  .
* OBTAIN A 4K BUFFER AREA IN ADDRESS SPACE TO BE
* USED TO UPDATE THE DATA IN THE HIPERSPACE WINDOW
  .
*  DECLARATION STATEMENTS
  .
HS1NAME  DC   CL8'MYHSNAME'        HIPERSPACE NAME
HS1STOK  DS   CL8                  HIPERSPACE STOKEN
HS1ORG   DS   F                    HIPERSPACE ORIGIN
ONEGIG   DC   F'262144'            MAXIMUM SIZE OF 1G IN BLOCKS
FOURK    DC   F'1'                 INITIAL SIZE OF 4K IN BLOCKS
OBJID    DS   CL8                  DIV OBJECT ID
OBJDD    DC   AL1(7),CL7'MYDD   '  DIV OBJECT DDNAME

The program can read the data in the hiperspace window to a buffer area in the address space through the HSPSERV SREAD macro. It can use the HSPALET parameter to gain faster access to and from expanded storage. The HSPSERV SWRITE macro can update the data and write changes back to the hiperspace. For an example of these operations, see Example of creating a standard hiperspace and using It.

Continuing the example, the following code saves the data in the hiperspace window on DASD and terminates the mapping.

* SAVE THE DATA IN THE HIPERSPACE WINDOW ON DASD AND END THE MAPPING
  .
  DIV     SAVE,ID=OBJID
  DIV     UNMAP,ID=OBJID,AREA=HS1ORG
  DIV     UNACCESS,ID=OBJID
  DIV     UNIDENTIFY,ID=OBJID
  .
* PROGRAM FINISHES USING THE DATA IN THE HIPERSPACE
  .
* DELETE THE HIPERSPACE
  .
  DSPSERV DELETE,STOKEN=HS1STOK