Using ALETs and Accessing Dataspaces with Dump/XDC

Just as classic z/XDC can access dataspaces in live storage, so can dump/XDC access dataspaces contained within a dump. Also like classic z/XDC, dump/XDC uses ALETs for accessing dataspaces.

To display dataspace storage, one way is as follows:

Issue LIST DSPACES ALL to report all the dataspaces contained within a dump.

Use an F shortcut against any listed dataspace to display its origin storage (X'00001000' in this case).

Create a simple equate (X for example) to help in referencing locations within the dataspace:

  • If the dspace has a zero origin, then just use EQUATE X +0 80000000 DATA
  • If the dspace's origin is X'1000', then use EQUATE X -1000 80000000 DATA

Then references to X+whatever becomes an easy way to reference location whatever in the dataspace to which X has been assigned. Example: FORMAT X+11B00 displays location X'00011B00' of the dataspace.


Another way is to use the currently designated execution thread's access registers. Example:

  • Suppose you've used the SET CURRENT tcbaddress (or CU shortcut) to assign the given TCB as the Current Execution Unit (CXU).
  • Suppose the task's R9 points to a location within a dataspace.
  • Suppose AR9 contains that dataspace's ALET.
  • Then FORMAT AR9? will display that storage. (z/XDC uses the ALET that's in AR9, together with the address with R9 to access the desired storage.)


Another way is to use an address expression containing z/XDC's ~ALET() built-in function, but I'm not going to get into the details here. See HELP FUNCTIONS ALET if you would like to learn more about this.


Of course, just like in classic z/XDC, you can assign both equates and dsect maps to dataspace storage. See HELP EQUATES and HELP MAPS for the details.