IBM OS/390 User Manual

IMS/ESA requires a Type 2 SVC in the MVS nucleus and a Type 4 SVC in
LPALIB.

IMS/ESA Resource Clean-up Module and ABEND Dump Formatting Routine must
be link-edited into SYS1.LPALIB.

IMSESA.RESLIB must be APF authorized.

Automatic field start calculation

Must code START= in the IMS/ESA DBD.

Automatic segment length calculation

Must code BYTES= in the IMS/ESA DBD.

FBA DASD Support

MVS does not support FBA (FIXed Block Architecture) DASD devices. This
requires changing the DEVICE= parameter of the DATASET statement to
the device type that will be used.

ACCESS Statement

The ACCESS statement is not supported in IMS/ESA. All parameters of the
ACCESS statement have equivalent function through parameters of the
DBD. This is provided in either DL/I or IMS/ESA DBDs. Therefore, the DBD
should be used for portability between DL/I IMS/ESA. The three types of
ACCESS statements and the required changes are:

R M N A M E =   ( m o d u l e ,

# of root anchor points,

# of CIs in root addressable area,

record insert limit in bytes)

data base root implied

SEQFIELD of root implied if PARENT=0 is coded

third subfield of the NAME parameter in the FIELD
statement defining the sequence field

separate DBD with ACCESS=INDEX needed

NAME= of LCHILD in index DBD

INDEX= of LCHILD in index DBD

In addition an LCHILD must be coded in the data DBD referencing an
index DBD.

separate DBD with ACCESS=INDEX needed

SEGM=target seg determined by which SEGM the LCHILD and XDFLD

follow in data DBD

SEGMENT= of XDFLD

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