cics_trianing class_03.ppsx

7/27/2019 CICS_Trianing Class_03.ppsx

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Program Preparation

CICS Training Class -03


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Required Steps

Preparing a COBOL-CICSProgram.

Write a program

Compile

Define the program in PPTtable with in CICS

Define the transactionto the program in PCTtable.

Executethe program with the Defined Transaction.


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Concepts to be Known

Before we start writing a program one should be clear with

TS!and Transaction

"ultitas#ing$ "ultithreading

%uasi&'eentranc(

Con)ersational"odes


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Task & Transaction

Task* a basic unit of wor# which is scheduled b( the operation

s(stem + CICS

Sending a map + 'ecei)ing a map

Transaction* Is an entit( which initiates execution of a tas#.

In CICS transaction is identified b( the transaction identifier

#nown as T',S&ID.

Trans-IDis a - character length alpha&numeric name but

should not start with character C/ which are actuall( used b(

the s(stem related transaction.


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ulti-Tasking

When CICS recei)es a re0uest to run a the program1 CICS

starts running instance of re0uested program for that user.

Simultaneousl( if CICS recei)es another re0uest to run the

same program+another program1 CICS starts running instanceof that re0uest program for that user also.

2i#e this CICS can able to handle thousands of re0uests1 can

able to run multiple tas#s simultaneousl(.

This capabilit( of executing multiple tas#s b( a single s(stemis called multitas#ing


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ulti-t!reading

"ultithreadingis sub&concept of multi&tas#ing.

"ultithreading is a techni0ue that almost a single cop( of a

program to be processed b( se)eral transaction concurrentl(

3orexample* one transaction ma( begin to execute an application

program1 while these happening another transaction ma( then

execute the same cop( of the application program


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"uasi- Reentranc#

The feature of storing the program data in a separate storage

area1 when there is a interruption and restoring the same state

is #nown as 'eentranc( but in CICS it4s called %uasi&

'eentranc( process.

When CICS recei)es 5st re0uest to a program1 CICS starts

executing that program1 at the same time1 another re0uest67nd8

recei)ed b( CICS1 which is more priorit(1 then CICS halts

processing of 5st re0uest$preser)eits state to separate

storage area and initiali9e the program. :nce second re0uest is

o)er. It initiali9es the program again $ restores 5st re0uest

state to this program and start executing the program.


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Terminal Con$ersation

Conversational* mode of dialogue between program and

terminal based on a combination of sending message and

recei)ing message within the same tas#.

Since human response is slower than the CP; speed a

significant amount of resource will be wasted


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CICS Consideration & Restrictions

5. "ust e)entuall( return control to CICS

chie)ed b( using 'ET;',Command

7. Should not code E,>I':,"E,T DI>ISI:,

So no C:,3I?:' I,P;T&:;TP;TSECTI:,

@. ,o 3I2ESECTI:,so no :PE, C2:SE 'ED :' otherC:B:2 file related )erb instead we use CICS read $ write

command

-. CCEPT DISP2A ST:P ';, and e)en ?:BC! area)oided. Stop run $ ?:BC! are sometimes included in

order to eliminate compiler diagnostic but ne)er executed at

all.


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Required Cop# %ooks

To write a C:B:2&CICSprogram we ma( be re0uired few

of the below mentioned C:PA B::!S

5. SA"B:2IC "ap7. D3=EIB2!

@. D3=ID

-. D3=B"SC


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S#mbolic ap

S(mbolic map can be generated at the time of B"S map compiler or

manuall(

This cop(boo# contains group item named MAPNAMEIis redefined

b( a group item named MAPNAMEO. The fields in the "P,"EI

group item are intended for use with input operations1 and the fields inthe "P,"E: group item are intended for use with output

operations.

The s(mbolic map contains a data field1 a length field1 an

attribute field1 and a field that indicates if the )alue of the fieldhas changed. The names for these fields are created b( adding

a onecharacter suffix to the label that was coded on the

D3="D3 macro in the mapset.


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'()I%*K Cop#book

EIB EXEC INTERFACE BLOCK contains some s(stem related

information to each tas# as exec interface bloc#

LIKE:

EIBAID Attention-id (1 BYTE)

EIBCALEN Length Of DFHCOAREA!COAREA("#($)%o&')

EIBDATE!EIBTIE Dte Ti&e *hen The T+, "tted

EIBFN F.n%tion Code Of The L+t Co&&nd

EIBRCODE Re+'on+e Code Of L+t Co&&nd

EIBTRNIDTn+%tion Id 1-$ Ch+

EIBTRID Te&in/-id 1-$ Ch+


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'(+I Cop# %ook

IDis used to initiate the tas# from the terminal

ll the ID #e(s are defined under D3=IDcop(boo#

ID #e(s*

PF Kes PA Kes ! Enter and clear kes

=,D2EID can be used to handle when an( ID #e( is

in)o#ed instead we can use EIBIDof EIB to wor# in

application program


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'(%SC+

IB" also supplies a standard cop( member1 named

D3=B"SC1 that defines man( attribute settings.

Aou can change the colour1 and protection attributes b(changing the field. To do this (ou should cop( the

D3=B"SC cop(boo# into wor#ing storage. This contains

definitions for attributes

e!". D3=B"S! to set a field to S!IP. Then mo)e there0uired attribute to the field.


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S), Command

EEC CICS

SE,D "P6"P8

"PSET6"PSET8

3':"6I,%"P5:8 FDT:,2A+"P:,2AG

C;'S:'6>2;E8F2'" H 3'EE!B H E'SE H 3'SET G

=,D2E+,:=,D2E

'ESP6WS&DT&ITE"8

E,DEEC.

Conditions # LENE$$% IN&$E'


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R)C)I)Command

EEC CICS 'ECEI>E

"P6"P,"E8

"PSET6"PSET ,"E8

I,T:6DT,"E8

2E,?T=6"S?&2E,8=,D2E+,:=,D2E

'ESP68

E,D&EEC.

Conditions # MAPFAIL% IN&$E'


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R)T.R, Command

EEC CICS 'ET;',

T',SID6,"E8

C:""'E6DT&>2;E8

2E,?T=6DT&>2;E8

E,D&EEC.

Conditions # LENE$$% IN&$E'


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C/%/* CICS Compilation

The C:B:2 CICS undergoes t(ree levelsof processing to

generates the 2oad "odule.

5. Translation process

D3=ECP7. Compilation I?AC'CT2

@. 2in#&edited IEW2+ =EW2


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Translation Process

,ow we ha)e a source code with C:B:2 CICSthen a

normal compilation process cannot be good enough

=ere we use a process #now as T',S2TI:,process to

remo)e the CICS command and replace with C:B:2

understandable code li#e C:""E,Tand C22

In this process a C:PAB::!D3=EIB2!will be included

with&in the lin#age section of the application program

The modified code then further get processed and generates the2:D":D;2E


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)ntries Required in CICS )n$ironment

The application program and the related map has to be defined in the PPT

table and a transaction id to initiate the tas# in pct table.

PPT ENT$)

CED DE3 "PSET6"PSET ,"E8 ?6?':;P ,"E8 CED I,S "PSET6"PSET ,"E8 ?6?':;P ,"E8 CED DE3 P':?'"6P':?'" ,"E8 ?6?':;P ,"E8 CED I,S P':?'"6P':?'" ,"E8 ?6?':;P ,"E8

PCT ENT$)

CED DE3 T',S6T',&ID8 P':?'"6P':?'" ,"E8?6?':;P ,"E8

CED I,S T',S6T',58 ?6?':;P ,"E8

To #now all entr( with in a group

CEDA DI *+*$O,P NAME


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T!ank 1ou

cics_trianing class_03.ppsx

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