Format of compat41 journal control label header, Journaling 646, Figure 72. format of journal control label header – IBM SC33-1683-02 User Manual

Page 678

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A graphical overview of the format of a general log, showing the format of a
complete block, is shown in Figure 71.

Format of COMPAT41 journal control label header

Each log block starts with a journal control label header. There is one journal
control label header per log block. It is 42 bytes long, and comprises a length field,
label header, and label prefix. The format of the journal control label header is
shown in Figure 72.

The label header part of the journal control label header is 10 bytes long, and its
format is shown in Figure 73 on page 647.

Log block

Log block

Log block

Journal

control

label

header

Journal

record

1

Journal

record

2

Journal

record

nn

Log block

Figure 71. Format of general log formatted using the COMPAT41 option

32

Fixed length

L a b e l p r e f i x

L a b e l h e a d e r

10

4

Le ngth of bl ock

N o t p r e s e n t e d u n l e s s t h e

c a l l e r i s r e a d i n g d a t a b l o c k s

r a t h e r t h a n r e c o r d s

Figure 72. Format of journal control label header

journaling

646

CICS TS for OS/390: CICS Customization Guide

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