How to determine DFSMSdss version, release, and modification level

Subsystems that invoke DFSMSdss dynamically must determine if DFSMSdss is installed on the system, and if it is, its version, release, and modification level, and features supported. A DFSMSdss-provided macro tries to determine the DFSMSdss version, release, and modification level and features supported and pass the requested information in a register.

ADRMCLVL (in SYS1.MACLIB) is an in-line executable assembler-language macro that can be invoked by a caller. The caller can be in problem program state and can have a user key. The caller must save registers 0, 1, 14, and 15 before invoking the macro. No other registers are disturbed. The caller can determine the installed level and features of DFSMSdss from the information returned in registers 1 and 14.

On return, register 1 contains information as follows:

If the release level of ADRDSSU cannot be determined, register 1 contains X'04000000'.
Otherwise, register 1 contains:
Byte 0
Product number, in binary:
- 0 = DFDSS
- 2 = MVS or OS/390® DFSMSdss
- 3 = z/OS® DFSMSdss
Byte 1
Version number, in binary:
- 1 = Version 1
- 2 = Version 2
Byte 2
When byte 0 is 0 or 2:
- Release number, in binary:
  1 = Release 1
  
  2 = Release 2
  
  3 = Release 3
  
  4 = Release 4
  
  5 = Release 5
  
  A = Release 10
When byte 0 is 3:
- Release number, in decimal:
  01 = Release 1
  
  02 = Release 2
  
  03 = Release 3
  
  04 = Release 4
  
  05 = Release 5
  
  10 = Release 10
  
  11 = Release 11
  
  12 = Release 12
Byte 3
Modification level, in binary:
- 0 = Modification level 0
- 1 = Modification level 1
- 2 = Modification level 2

On return, register 14 contains the following information:

If the release level of ADRDSSU is less than DFSMSdss Version 1, Release 4, Modification level 0, then the contents of register 14 are unpredictable.
Otherwise, register 14 contains the following:
Byte 0
Feature Flags:
- Bit 0, when set to 1, means DFSMSdss cross-memory Application Programming Interface support for concurrent copy is available.
- Bit 1, when set to 1, means DFSMSdss will use the expanded EIREC14 record introduced with the ZCOMPRESS keyword support (OA42238).
- Bits 2–7 are reserved.
Bytes 1–3

Reserved.