Here are CICS mainframe interview questions and answers for freshers as well as experienced candidates to get their dream job.
1. What is CICS ?
CICS stands for Customer Information Control System and happens to be software that monitors telecommunications from IBM. The mainframe operating systems of IBM are time-sharing and batch.
2. What is the primary aspect of CICS?
CICS basically deals with the execution as well as development of online applications. It establishes a communication channel through the terminal and facilitates the receiving as well as sending of data that is formatted. One of the primary aspects of CICS is the accessibility of database as well as the files that they contain.
3. Mention one alternative aspect of CICS?
CICS happens to be a batch job itself and runs on high priority in the operating system. Thus, there is a demarcated CICS region in which the programs are adequately scheduled by CICS.
4. What is meant by PPT and what are its uses?
PPT (Program Processing Table): – It consists of a list that has all the names of the programs in it along with maps. Furthermore, it tells us whether the version that is absolutely recent as available as a program in CICS or a fresh copy of the program is supposed to be loaded.
5. Comment on TCT and RCT.
TCT stands for Terminal Control Table and is a compilation of all the respective terminals.
RCT, on the other hand, stands for Resource Control Table is a compilation of plan names of DB2 along with the transaction identifier.
6. Differentiate between PCT and FCT.
PCT stands for Program Control Table and it has a complete list of transaction identifiers that are paired to respective corresponding programs.
FCT, on the other hand, stands for File Control Table has a complete list of all the files that have been used by CICS along with their status and record length.
7. What is meant by a CICS task?
A CICS task is a one-time execution of a certain CICS transaction. This process starts when the key is entered into the transaction, and the enter key is pressed. The execution process continues till the program returns the control back to CICS.
8. What do you mean by CEMT?
CEMT refers to Master Terminal Transaction. It happens to be an ID for system transaction and inquires about the status. Furthermore, it changes the status of the resources.
9. Give the definition of COMMAREA ?
COMMAREA is commonly termed as a communication area as it happens to be for temporary storage area. It is used as a passing medium for data amongst multiple programs that are loaded by a set of transactions or a particular transaction.
10. Name a few CICS programs which are generally used ?
The CICS programs which we generally use are:
- File Control
- Terminal Control
- Storage Control
- Task Control
11. What is meant by a ‘Transid’?
Transid stands for transaction identifier. In order to invoke a task of CICS, this character code consisting of four letters will be used.
12. Explain the use of DCT ?
DCTs stands for Destination Control Tables that are aesthetically used in CICS to define TDQs.
13. In the EIB block of CICS, highlight the names of few of the important fields?
Few of the important fields in the EIB block of CICS are EIBCALEN, EIBRESP, EIBTASK, EIBRRCDE, EIBTIME and EIBDATE.
14. Can dynamic calls be used in CICS?
Yes. Dynamic calls can be used in CICS and as per the procedure, the user has to define the call routine in a PPT and CALL identifier must be used by the calling program.
15. Name at least one of the ways by which a transaction can be terminated?
Use the command EXEC CICS SYNCPOINT and assume it as LUW. By this process, there will not be a termination of Xn, but the transaction will surely be terminated.
16. Highlight the points of differences between XCTL and START?
XCTL acts as a medium through which you can pass the control through the identical task to another program. XCTL happens to be a program control command.
17. How ENQ and DEQ used in CICS?
ENQ and DEQ are parts of task control commands that are used in making a resource serially recyclable.
18. Give certain situations where NEWCOPY is obligatory?
NEWCOPY is necessarily required in CICS when a particular program has been run at least once, or many times in CICS and then recompiled or changed.
19. Can a CICS code be a part of a copybook? If so, then what are the outcomes after compilation?
A CICS code can easily be a part of a copybook, but reprocessing has to be done after compilation process.
20. With the use of an alternate index, how is a VSAM file accessed?
VSAM file can be accessed through path. All we have to do is declare a path as a form of FCT and then use File Control Commands on it.
21. What is meant by an AICA ABEND?
AICA ABEND is just a Runaway Task that is executed at a later stage.
22. Can ESDS files be accessed from CICS?
Yes. It is possible to access ESDS files straight from CICS.
23. What is the procedure to solve an ASRA ABEND?
All you have to do is start with the CEBR and then call for instructions of offsets.
24. How errors are handled in CICS programs?
In order to handle the errors, you will need to check the EIBRESP after calling the program. An alternative option would be to put the HANDLE condition to use.
25. Highlight the difference between a symbolic map and physical map?
Symbolic map happens to be a data structure, whereas a physical map is basically a load module.
26. What is the difference between SEND MAP DATAONLY and SEND MAP MAPONLY ?
SEND MAP DATAONLY: – Through this, the data is sent without the layout. It is used in order to refresh the data that comes to the screen.
SEND MAP MAPONLY: – Through this, only the map is sent and not the data. Whenever we are in the process of sending menu screens, the data is never sent.
27. What is meant by MDT? Furthermore, comment on FRSET and FSET ?
MDT stands for Modified Data Tag. If the modification of the field has to be done on the screen, then MDT acts as a bit of an attribute byte. MDT comes into play during an input operation.
FRSET is used to reset MDT. The field will be sent till the time, the MDT has been set again by FRSET. FSET is in charge of ensuring that field is transmitted by MDT. FSET comes into play during an output operation.
28. Explain how DSECT parameter is used in BMS ?
DSECT parameter is used in BMS in order to give shape to a symbolic map.
29. Mention the content that is present inside a PPT ?
Source, Length, Lang, Use Count, Rescount DFHRPL number are the contents that are present inside a PPT.
30. Can QSAM files be accessed from CICS?
No. It is not possible to access a QSAM file from CICS.
31. Can ESDS files be accessed from CICS?
Yes. It is possible to access ESDS files from CICS.
32. In a CICS program, how will you read a VSAM file?
VSAM file can be easily read in a CICS program using File Control Commands. The four types of commands for this process are forward, backward, random and sequential.
33. What does EIB mean in CICS?
EIB stands for Execute Interface Block. One EIB is attached to each and every task and this stays with the task till its execution. The EIB of all the programs remains unchanged throughout the process. In the read mode of any COBOL program, EIB fields can be accessed.
34. What does a CICS translator do?
There is a linkage area associated with every program. In this area, the EIB block is generated by the CICS translator.
35. What is meant by an attribute byte?
An attribute byte is used in CICS to define a particular transmission field or display. It contributes to the output field of the program.
36. List out all the tables that are a part of CICS ?
The tables that are a part of CICS are PPT, SIT, PCT, JCT, FCT, SNT, DCT, SRT, RCT and TCT.
37. Explain the uses that are associated to TSQ and TDQ ?
TSQ and TDQ are actively used in CICS for temporary data storage purpose.
38. Can a TSQ of one particular transaction be accessed from an alternate transaction?
Yes. It is possible for a TSQ to be accessed from an alternate transaction provided as both of the transactions are running in the identical regions.
39. In a particular CICS program, what is the procedure to allocate dynamic memory?
All you have to do is use a GETMAIN in order to dynamically allocate memory in CICS.
40. What is the procedure to read a statement from TSQ?
In order to read a statement from TSQ, you will have to use Temporary Storage Read Command.
41. Whenever a CICS program goes through a compilation process, there is always some extra code that is added to the program. Where exactly does this new piece of code go to and what is it termed as ?
This new piece of code goes to DFHEIBLK, and it is commonly termed as DFHCOMMAREA.
42. If we wish to create BMS executable, what are the basic steps that the user has to go through?
In order to create BMS executable, the user has to assemble in order to create CSECT, as well as Link.
43. RECEIVE consists of BUFFER option in it. What is the significance of this option?
BUFFER option connects with terminal buffer and fetches the total data-stream.
44. In case if the user inputs the characters which turn out to be uppercase, then what is the procedure to close that condition?
The easiest way to turn off the uppercase option is to make use of ASIS option that is available on RECEIVE.
45. If we say that BMS Length of field = 0, then what does that mean?
This basically points to the fact that the data was not properly entered in a given field.
46. Is Length = 0 sufficient to ascertain that the field has been modified?
No. There is no point in checking the possibility of modification of field using Length = 0 as it requires ERASE OFF.
47. Let us say you have a collection of multiple maps in CICS. So if you are asked to determine the exact storage space that is available in a symbolic map, then how will you compute it?
Storage of the maps is always redefined before any other aspects, and this is the reason why the storage of largest map will naturally be more than all the other maps that are available to the user.
48. Explain how PA key is different from PF key?
The primary function of PF keys is to start the transmission of data that has been modified PA keys are used only to wake the task up. Henceforth, the starting process of transmission of data requires both PF key as well as PA key.
49. Explain the primary significance of intra-partition and extra-partition TDQs ?
CICS has various batch regions in it, and there are certain datasets, which are primarily used for communication channels between CICS and the batch regions that fall out of the domain of CICS. Extra-partition TDQs help in this aforementioned process.
On the contrary, intra-partition TDQs are channels of communication that are present within the region of CICS. These channels are divided into multiple queues.
50. Every map is categorized into multiple fields, and there are three common working storage fields present for each of these respective fields. Mention those?
The three common working storage fields in CICS are attribute, length and output/input field. Without these three fields, the maps cannot be categorized respectively.
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