PARMOD=31 expansions of the DMS macros usually differ from the PARMOD=24 expansions, which may occasionally result in base register overflows, etc. All PARMOD=31 expansions begin with an 8-byte standard header. This standard header is described in the appendix of the "DMS Macros" manual [1 (Related publications)].
Access methods SAM and ISAM
All action macros generated with the 31-bit interface destroy the contents of register 15 in all cases. The contents of registers 0, 1 and 14 may also be destroyed, e.g. in error situations.
The retrieval address supported by SAM can be found, for the 31-bit interface, in the FCB fields ID1BLK# (block counter) and ID1REC# (record counter). In the 24-bit TU FCB, this address is kept in field ID1RPTR (see section "FCB retrieval address").