IBM SC34-7012-01 Programming for recovery, Resolving retained locks, Moving recoverable data

Input extrapartition data sets	.	.	134
Output extrapartition data sets . . . .	.	.	135
Using post-initialization (PLTPI) programs	.	. 135
Recovery for temporary storage	.	.	135
Backward recovery	.	.	135
Forward recovery	.	.	136
Recovery for Web services	.	.	136

Configuring CICS to support persistent

messages . . . . . . . . . . . . . . 136

Defining local queues in a service provider .	.	137
Persistent message processing	.	138

Chapter 13. Programming for recovery	141
Designing applications for recovery	.	141
Splitting the application into transactions . .	.	141
SAA-compatible applications	.	143
Program design	.	143
Dividing transactions into units of work . .	. 143
Processing dialogs with users	.	144

Mechanisms for passing data between

transactions . . . . . . . . . . . . . 145 Designing to avoid transaction deadlocks . . . 146

Implications of interval control START requests	147
Implications of automatic task initiation (TD
trigger level)	148
Implications of presenting large amounts of data
to the user	148

Managing transaction and system failures . . . . 149

Transaction failures	.	.	.	149
System failures	.	.	.	151
Handling abends and program level abend exits				151
Processing the IOERR condition . . .	.	.	. 152
START TRANSID commands . . . .	.	.	. 153
PL/I programs and error handling . .	.	.	. 153

Locking (enqueuing on) resources in application programs . . . . . . . . . . . . . . . 153

Implicit locking for files	.	154
Implicit enqueuing on logically recoverable TD
destinations	.	157
Implicit enqueuing on recoverable temporary
storage queues	.	157

Implicit enqueuing on DL/I databases with
DBCTL . . .	. .	.	. .	. . . . .	.	158
Explicit enqueuing (by the application
programmer) .	. .	.	. .	. . . . .	.	158

Possibility of transaction deadlock . . . .	.	159
User exits for transaction backout	.	160
Where you can add your own code . . . . . 160
XRCINIT exit	.	161
XRCINPT exit	.	161
XFCBFAIL global user exit	.	161
XFCLDEL global user exit	.	162
XFCBOVER global user exit	. 162
XFCBOUT global user exit	. 162
Coding transaction backout exits	.	162

Chapter 14. Using a program error program (PEP) . . . . . . . . . . . 163 The CICS-supplied PEP . . . . . . . . . . 163 Your own PEP . . . . . . . . . . . . . 164

Omitting the PEP . . . . . . . . . . . . 165

Chapter 15. Resolving retained locks

on recoverable resources . . . . . . 167 Quiescing RLS data sets . . . . . . . . . . 167 The RLS quiesce and unquiesce functions . . . 168 Switching from RLS to non-RLS access mode. . . 172 Exception for read-only operations . . . . . 172

What can prevent a switch to non-RLS access mode? . . . . . . . . . . . . . . . 173 Resolving retained locks before opening data

sets in non-RLS mode . . . . . . . . . 174 Resolving retained locks and preserving data integrity . . . . . . . . . . . . . . 176

Choosing data availability over data integrity		177
The batch-enabling sample programs . . .	. 178
CEMT command examples	. 178
A special case: lost locks	.	180
Overriding retained locks	.	180

Coupling facility data table retained locks . . . . 182

Chapter 16. Moving recoverable data
sets that have retained locks . . .	. 183
Procedure for moving a data set with retained
locks	. 183
Using the REPRO method	. 183
Using the EXPORT and IMPORT functions .	. 185
Rebuilding alternate indexes	. 186

Chapter 17. Forward recovery

procedures . . . . . . . . . . . . 187 Forward recovery of data sets accessed in RLS

mode . . . . . . . . . . . . . . . . 187

Recovery of data set with volume still available	188
Recovery of data set with loss of volume . .	. 189

Forward recovery of data sets accessed in non-RLS mode . . . . . . . . . . . . . . . . 198 Procedure for failed RLS mode forward recovery operation . . . . . . . . . . . . . . . 198 Procedure for failed non-RLS mode forward recovery operation . . . . . . . . . . . 201

Chapter 18. Backup-while-open (BWO)	203
BWO and concurrent copy	. 203
BWO and backups	. 203
BWO requirements	. 204
Hardware requirements	. 205
Which data sets are eligible for BWO . . . .	. 205
How you request BWO	. 206
Specifying BWO using access method services	206

Specifying BWO on CICS file resource

definitions . . . . . . . . . . . . . 207

Removing BWO attributes . . . .	. . .	.	. 208
Systems administration	. . .	.	.	208
BWO processing	. . .	.	.	209
File opening	. . .	.	.	210
File closing (non-RLS mode) . .	. . .	.	.	212
Shutdown and restart . . . .	. . .	.	.	213
Data set backup and restore . .	. . .	.	.	213

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