What is LPAR?Ans: OS/400 Version 4, introduced a feature LPAR (Logical PARtitioning) which facilitates running multiple operating systems simultaneously on one IBM System i unit ensuring that one OS doesnt interfere others system resources/memory.

What is library is AS400? What are the types of library?Ans: When we execute a command or call a program, the AS/400 must know where to find the command or program and the answer is library. A Library is a collection of objects. QSYS is the only library that contains other library. QSYS is the root library where the entire user defined/ system defined library is created. System supplied libraries begin with the letter "Q" or "#".Library list types:System library: All IBM supplied library e.g. QSYS, QHLPSYS, QUSRSYSProduct Library: Whenever Ibm product is used it is added to the library automatically and is removed itself when the job completes.Current Library: Current library is the working library i.e. all the work done by you is stored in current library. User Library: Non-IBM supplied i.e. created by the user. Which library gets first loaded into the system when we login?Ans: QSYSIs QGPL a user library or system library?Ans: Its a user library. How can we see all the objects and its sizes in a library?Ans: By using the command DSPLIB.7. What is source physical file?Ans: Source physical file is a file which contains the sources of different types of objects. There can be up to 32768 members. Source physical file is an object. But the source member is not an object. When we compile the member, the object is created for that source. Command used is CRTSRCPF.CRTSRCPF FILE(IROBO1/QRPGSRC) RCDLEN(112) TEXT('SOURCE PHYSICAL FILE)8. How to see all members of a file?Ans: By using the command shown below:DSPFD FILE(IROBO1/QRPGLESRC) TYPE(*MBRLIST)9. How to see all record formats used in a file?Ans: By using the command shown below:DSPFD FILE(IROBO1/QRPGLESRC) TYPE(*RCDFMT)10. How to change the record size of a physical file?Ans: By using the command below:CHGPF FILE(AMITNEM/OBJ) SRCFILE(AMINEM/QDDSSRC) SRCMBR(OBJ_SRC)12. How to refer another file to define a new field in a physical file?Ans: below is an example, we are going to use the file REFER to get the field definition for new file.USE OF REFERENCE 13. Can LEVEL CHECK ERROR occur if we do CHGPF?Ans: It depends on the value that we have set for LVLCHK (Record format level check) attribute. If its value is *YES then the record format level identifier is checked when the file is opened and if it doesnt match it throws the error. If its value is *NO, then the record format level identifier is not checked, hence no error.1. What is the use of RGZPFM? Give example of RGZPFM.Reorganize physical file member(RGZPFM)We generally use RGZPFM to reuse the deleted records of a file for future insert operation. The data in a file in inserted sequentially. If we delete some in between records, then those freed spaces wont be used for inserting new record. Like this, the toll of space accumulated by deleted records goes on and we cannot use them until and unless we run RGZPFM command to reorganize the space.Once we delete the records the relative record number of the records gets changed due to reorganization of file.Suppose a file is used in most of the programs based on its key value. If we want to change the access path of this file from sequential to keyed or from one key value to another key value, then we can go for RGZPFM How to create a multi-member physical file?TO ADD A NEW MEMBER TO THE FILE USING ADDPFMADDPFM FILE(AMINEM/ACCOUNT) MBR(MBR2) Member MBR2 added to file ACCOUNT in AMINEM. STRDFU => SELECT member as MBR2 to add record in the new member.TO ADD A NEW MEMBER TO THE FILE USING CPYFCPYF FROMFILE(AMINEM/ACCOUNT) TOFILE(AMINEM/ACCOUNT) FROMMBR(ACCOUNT) TOMBR (MBR3) MBROPT(*ADD) CRTFILE(*NO) FROMRCD(1) NBRRCDS(3) Member MBR3 added to file ACCOUNT in AMINEM. 3 records copied from member ACCOUNT. 1. What is logical file in AS400? What are the types of logical file?Logical file Logical file does not occupy any memory. One or more logical file can be derived from a single physical file. It simply contains the record selection definition and when accessed retrieves the records from the physical file to which it refers. A logical file can contain up to 32 record formats. It selects records dynamically. It cannot exist without a physical file. We can filter the data with criteria by using select and omit command. A logical file does not contain any data but provides the VIEWS of the data to satisfy end-users needs.There are two types of Logical file1) Non-join logical file2) Join logical file1) Non-join logical fileNon-join logical files can either be a simple logical file, which contains only one record format or a multiple record format logical file, which contains more than one Record format.Logical files can be derived from 1 to 32 physical files and so a logical file can have a maximum of 32 record formats.Single record format Non-join logical file:If a logical file is derived from single physical file it is called simple logical file.Multiple record format Non-join logical file: Multiple record non-join logical files will select records from 2 or more physical files by referring to only one logical file. Each record format is always associated with one or more physical file The same PF can be used in more than one record format2. What is DYNSLT? DYNSLT: Use this file-level keyword to indicate that the selection and omission tests specified in the file (using select/omit specifications) are done at processing time. This keyword specifies dynamic select/omit rather than access path select/omit. Only a Physical file contains data. Logical files just contain pointers for processing the data in a specific sequence and/or subset of data.When a record is added/changed/deleted in a physical file, the system has to put a lock on it and then go out to check and update any logical files before it can release the lock. While the amount of time to do this is hardly measurable, it can be significant if massive batch updates are done to a file.If you are using the Select/Omit option in your DDS and using DYNSLT, the above process does not need to be done at record update time. Where this is beneficial is when your selection process includes almost all the records in the file. Now when you process using DYNSLT, it will read all the records in the file, but do the selection of which records to process at that time rather than having done all the maintenance ahead of time.3. What is the Difference between access path and Dynamic select?Ans: Dynamic select occurs whenever the program reads file. But access path occurs before the file is read (but not necessarily). 4. What is the use of JDUPSEQ in AS400? JDUPSEQThis joinlevel keyword is used to specify the order in which records with duplicate join fields are presented when the JLF is read.The format for this keyword is:JDUPSEQ (Sequencing field-name [*DESCEND]) This keyword has no effect on the ordering of records with unique keys. If *DESCEND is not specified then the default is sequencing in ascending order.5. What is the use of JDFTVAL in AS400?JDFTVAL When this file-level keyword is used the system provides default values for all for fields when a join to a secondary file does not produce any records. If this keyword is not specified a record in the primary file for which there is no corresponding record in the secondary file is skipped.1. What is the difference between non-join logical files and join logical files?Non join logical fileJoin logical file

We can insert or delete or update records using non-logical file. Insertion, updating or deletion of records is not possible in join logical files.

DFU can be used to display non-join logical file.DFU is not available

1-32 record format is specifiedOnly one record format can be specified

Commitment control is usedCommitment control cannot be used.

2. What is the difference between physical file and logical file? Physical fileLogical file

1. Occupies the portion of memory. Its containing data. Does not occupy any memory space. Does not contain any data.

2. A physical file contains one record formatA logical file can contain up to 32 record formats.

3.Can be exist even without LFCant exist without PF

4. If you delete a LF, the PF cant be deletedIf you delete a LF, the PF cant be deleted

5.CRTPF command is used to create such objectCRTLF command is used to create such type object

4. What are the record format field mapping options in CPYF?Record format field mapping (FMT)*MAPFields with the same name in the from-file and to-file record formats are copied, and any fields in the to-file that do not exist in the from-file format are set to the default value specified on the DFT keyword for the data description specification (DDS) of the to-file or zero for numeric fields, blanks for character fields, current date/time for date/time fields, or null value for null-capable fields.If *MAP is specified, *DROP can also be specified.*DROP This value must be specified for field-level mapping if any of the field names in the from-file record format do not exist in the to-file format. If *DROP is specified, *MAP can also be specified. When *DROP is specified, all the field names that exist in both record formats must have the same attributes and relative positions in the from-file and to-file record formats, or *MAP must also be specified. Null values are copied.*NOCHK If the record formats of the database files are different, the copy operation continues despite the differences. Record data is copied directly (left to right) from one file to the other. FMTOPT (*NOCHK) is required when copying all record formats from a logical file with multiple formats (when RCDFMT (*ALL) is specified) to a physical file that is of the same type (source or data) as the from-file.*CVTSRC This value is used to copy between database files, from a source file to a data file, or from a data file to a source file. It is valid only when the from-file and to-file are different types (source and data). 5. What is the Difference between CRTDUPOBJ and COPYF?Ans: In CRTDUPOBJ for a logical file the created duplicate file will be also logical file and for a physical file the created file will also be a physical file. Even the record format identifier will also be the same. While in case of COPYF, if we are copying a logical file then the created file be a physical file not a logical file.6. What is access path in AS400?Access path Access path describes the order in which records are to be read. Access paths can be kept on the system permanently (such as physical or logical file) or temporarily. OPNQRYF command may create a temporary access path for use one time, and then discard the access path. 7. What are the types of access path? How to change the access path of a file? Types of Access Path Arrival sequence access path Keyed sequence access path Arrival sequence access path Sequentially, where each record is taken from the next sequential physical position in the file. Directly by relative records number, where the record number is identified by its position from the start of the file. Keyed sequence access path It is based on the contents of the key fields as defined in DDS. This type of access path is updated in the contents of a key field is changed. There are three ways of bounding the access path:o Immediateo Rebuildo DelayedChange access path of a file: We use CHGPF to change the access path maintenance parameter as shown below. ***Note: RGZPFM can also be used to change the access path of a file.The three ways of maintaining access paths of closed files are: *IMMED: Immediate maintenance of an access path means that the access path is maintained as changes are made to its associated data, regardless if the file is open. *REBLD: Rebuild maintenance of an access path means that the access path is only maintained while the file is open, not when the file is closed; the access path is rebuilt when the file is opened the next time. When a file with rebuild maintenance is closed, the system stops maintaining the access path. When the file is opened again, the access path is totally rebuilt. *DLY: Delayed maintenance of an access path means that any maintenance for the access path is done after the file member is opened the next time and while it remains open. However, the access path is not rebuilt as it is with rebuild maintenance. Updates to the access path are collected from the time the member is closed until it is opened again. When it is opened, only the collected changes are merged into the access path.8. What is the default access path of a file? If you do not specify the type of maintenance for a file, the default is immediate maintenance.1. What is the maximum number of fields that can be in a file? Maximum no of fields included in a PF is 8000.2. Maximum no of parameter passed in a RPG? Maximum no of parameter passed in RPG is 255.3. Maximum no of parameter passed in a CL? Maximum no of parameter passed in CL is 40.What is the maximum number of record format in a physical file? -- 1What is the maximum number of record format in a join logical file? Ans: 1What is the maximum number of record format in non-join logical file? Ans: 327. What is the maximum number of record format in a display file? 1024 8. What is the maximum number of record format in a subfile? 512What is the maximum no of key fields in file? Ans: 120 How to reset dates in SEU?Changing Session Defaults (F13)Before you start entering the source code make sure the session environment for SEU is set-up as you wanted.In Session environment you can edit the session attributes highlighted below.We can change the session default that will be used during source entry/editing process.How to search records based on date as searching criteria in SEU?FIND/CHANGE CommandShift-F2We can search a string or search for date in source (included/excluded/all).It has been discussed previously also in X line command section.An alternative way is to directly give the SEU command entry as F E A 8. This command will find(F) records with character E at position 8 in all(A) source. 12. How to see another member source in the same SEU? Specifying the Browse/Copy Option SHIFT+F31. What is array in AS400? What are the types of array?Array is collection of elements of same data type. Types of Array1)Compile time array2)Pre-runtime array3)Run time array2. What is compile time array in AS400? Give example of compile time array.Compile time arrayThe compile time array means the elements of the array will be loaded before the execution of the programs i.e. at compile time.The value will be static.We must declare in keyword command DIM (), CTDATA (), and PERRCD ().DIM()represents the size of the array.CTDATA()represents that it is compile time array.PERRCD()represents the number of entries in one array record.Dim=row i* col je.g.PERRCD=2, NO. OF ROWS=3, THEN DIM = PERRCD*NO. OF ROWS=6We mention the array element just after the last statement of the program.3. What is Pre run time array in AS400? Give example of Pre run time array.Pre-runtime arrayThere are some limitations of compile time array. E.g. If we want to change the value of an array element, we need to make changes in the program source code where the arrays element is defined and then recompile the program.In pre-runtime array, we maintain the array element in separate file. Hence, if we are making any change in array element we can just change this file containing the array element; we dont need to compile the source program again and again as in compile time array.The file that stores the array element must be defined in the F specs with T as File Designation entry.Record length is also a mandatory entry in F spec.length of record = Perrcd *size of 1 elementThe file is opened at program initialization. At that time the array loads from this external file.To define the array in our program, we use keyword FROMFILE() instead of CTDATA().Example- IFlat-File USED: Flat014. What is run time array in AS400? Give example of run time array.Run time arrayThe run time array means the value will be loaded during the runtime only.The value will be dynamic.What is indicator data structure in AS400? Give example indicator data structure.The indicator data structure is used to rename the indicators used in our program with the name that is more meaningful and understanding.If we want to use indicator data structure in our program thenINDARAis a mandatory keyword in the display file used.How can we create subsystem in AS400?Steps of creating the subsystemCreate Subsystem description (CRTSBSD)

First of all we create subsystem description as below:

CRTSBSD SBSD (AMINEM/MYSBSD) POOLS ((2 *BASE)) MAXJOBS(2) TEXT('My subsystem description')

Here, the subsystem job will run in pool 2 and will use *BASE for main memory storage. There can maximum of 2 jobs inside the subsystem at a time.

Create Job queue (CRTJOBQ)

Then we create a job queue as below:

CRTJOBQ JOBQ (AMINEM/MYJOBQ) TEXT('My job queue')

Add Job Queue Entry (ADDJOBQE)

Once the job queue is created, then we attach the (ADDJOBQE) command, as follows:

ADDJOBQE SBSD (AMINEM/MYSBSD) JOBQ (AMINEM/MYJOBQ) MAXACT (1)

MAXACT denotes the number of the jobs that can be process at the same time.

Create Class (CRTCLS)

Class defines the run time attribute e.g. Run priority, Time slice, Default wait time, Maximum temporary storage etc.

CRTCLS CLS(AMINEM/MYCLS) RUNPTY(40)

Add Routing Entry (ADDRTGE)

ADDRTGE SBSD(AMINEM/MYSBSD) SEQNBR(9999) CMPVAL(*ANY) PGM(SYS/QCMD) CLS(AMINEM/MYCLS)

Start Subsystem (STRSBS)

STRSBS SBSD(AMINEM/MYSBSD)

Once the subsystem is started it can be used to submit the job.

2. What is data queue in AS400? Give example of data queue.

Data Queue

It is used for making asynchronous communication between the two jobs. If we are sending data from one job to another using data queue using QSNDDTAQ API, but at that time the receiver job is not active, then the data will be there in the queue and whenever the receiver job becomes active, it retrieves the data using the QRCVDTAQ API.

It facilitates fastest communication compared to when we use other things to communicate like dataarea, message queue or database files.

It can yet be used for synchronous communication also or within the same job.

We use APIs to make communication e.g. QSNDDTAQ, QRCVDTAQ.

The content of the data queue is messages in free format.

The messages on the data queue is stored in *FIFO, *LIFO or *KEYED. *KEYED means the messages can be retrieved using key value associated with the messages. In case of *KEYED we need to mention key length also.

First create the data queue by using CRTDAQ command

Data query is nothing but a queue in which are program can send a data and other program or the same program can receive the program. QSNDDTAQ is stored in QSYS.

We can create data queue on local system or on remote system by making the data queue type as *DDM. By default it will be *STD. In case of DDM data queue, we need to mention Remote data queue name(RMTDTAQ) and remote system name(RMTLOCNAME) also as parameter.

QSNDDTAQ

By using this command sent data same / another program.

QSNDDTAQ PARM (QUEUE-NAME LIB &LEN &DAT)

QRCVDTAQ

By using this command receive data same /another program

QRCVDTAQ PARM (QUEUE-NAME LIB &LEN &DAT &WAIT)

1. Create Stream File from PF and Create PF from Stream File

(1) CRTDIR DIR('''/HOME/DIR1''')

(2) COPY ANY DATABASE FILE IN QTEMP AND CREATE FILE AMINEM/MAST.

(3) CPYTOIMPF FROMFILE(AMINEM/MAST) TOSTMF('/HOME/DIR1/XXX.TXT') RCDDLM(*CR)

STRDLM(' ') FLDDLM('|')

All records copied from file MAST in AMINEM.

(4) WRKLNK '/HOME/DIR1/XXX.TXT' 1. What is data structure in AS400? What is the use of data structure? Ans: DATA STRUCTURE Data structure in general means a structure of different data type. Data structure is specified in the Input Specification of an RPG 3 Program whereas in RPG 1V we specify it in 'D' specification. Data Structure is used-1.To break fields into subfields2.To Group fields3.To change the format of the field4.To Group non-contiguous data into contiguous format 5.To convert data.2. What are the types of data structure in AS400? Give example of data structure?Ans: Below are the types of data structures in as/400:I.PROGRAM DESCRIBED DATA STRUCTUREII.EXTERNALLY DESCRIBED DATASTRUCTUREIII.MULTIPLE OCCURENCE DATASTRUCTUREIV.INDICATOR DATA STRUCTUREV.DATA AREA DATA STRUCTURE (SPECIFIED IN 'U')VI.PROGRAMME STATUS DATASTRUCTURE (SPECIFIED IN 'S')VII.FILE INFORMATION DATASTRUCTURE3. What is program status data structure(PSDS) in AS400? Give example if PSDS.Ans: A program status data structure (PSDS) can be defined to make program exception/error information available to the program so that the necessary action can be taken for the unhandled exception. The exception /errors can beDivide by zero, array index out-of-bound, Invalid Date, Time or Timestamp value.The PSDS must be defined in the main source section; therefore, there is only one PSDS per module.4. What is file information data structure(INFDS) in AS400? Give example if INFDS.Ans: A file information data structure (INFDS) can be defined for each file to make file exception/error and file feedback information available to the program.5. What is indicator data structure in AS400? Give example indicator data structure.The indicator data structure is used to rename the indicators used in our program with the name that is more meaningful and understanding.If we want to use indicator data structure in our program thenINDARAis a mandatory keyword in the display file used.

2. What is journaling? Give example of journaling?JournalingJournaling, generally speaking, is a process of recording activity.On the iSeries, journaling refers to the process of recording object activity.Journaling on the iSeries typically involves the recording of the activity related to files, namely, physical files. When a file is being journaled, activity such as file-opens, file-closes and data updates are recorded.Set up journaling1.Use theCreate Journal Receiver(CRTJRNRCV) command to create a journal receiver.The journal receiver is where the journalentriesare actually recorded. The journal "connects" the receiver to the file.It's a good habit to name the journal receiver the same as the journal, plus a numeric suffix such as 0 or 1.Also, you should put journal receivers in the same library as the file.2.Create a journal.Use theCreate Journal(CRTJRN) command to create a journal and specify the receiver created in step 1. Although you can journal multiple files to the same journal (and, in some cases, that is actually preferable), you will generally want to have a journal "serving" a single file.3.Start journaling the file.This is done by using theStart Journal Physical File(STRJRNPF) command. This is how you associate a file to a journal. Once the association is made, the system will record in the journal receiver a copy of any record added, updated or deleted from the file. Other activity, such as when the file is opened and closed, can also be recorded in the journal receiver if you choose by selecting the appropriate options on theSTRJRNPFcommand.Message subfile Message subfile as the name signifies is a subfile of messages. It is a special subfile specially designed to hold messages. Message subfile loads itself automatically at runtime loads with the messages from program message queue to display it on the screen. To load the subfile we simply fill the message queue with the messages and link the subfile with that message queue. Similarly to clear the subfile, we clear the message queue. Message subfile can be used in a case we want to display multiple error/information messages at the same time on the screen or other way it can be used to display additional information for a particular error message like what should be done in a case it appears. More precisely we can say that by using this we can display 2nd level messages by programming with great ease. How many messages we want to display on the screen, it depends on SFLPAG value.6. Give example of EDTCDE keyword in as400?EDTCDE (Edit Code) This keyword is used to edit output-capable numeric fields. Edit code, depending upon the data type edits the contents. e.g. By using it, the field can be punctuated with commas and periods. E.g. 1,000.50 Negative values can be printed with a minus sign or CR to the right. E.g. 100.50CR, 100.50- A currency symbol can be printed with the help of this keyword. E.g. 100.50$ The value can be padded with zeros at the left instead of blank padded. E.g. To print 000125.50 instead of XXX125.50 (where X=blank) Date can be formatted with the keyword EDTCDE(Y). E.g. 1/12/99 Zero values can be printed as zeros or blanks as per the requirement. Use EDTCDE(Z) to remove , separator in the field value.66. Give example of EDTWRD keyword in AS400.EDTWRDSometimes we are not able to get the desire editing result by EDTCDE. In that case it is better to go for EDTWRD.In the EDTWRD parameter we specify the format matching the required data.This keyword is valid only for numeric field (Specified with Y data type).Before EDTWRD, Value of C_FLD001= .12After EDTWRD, Value of C_FLD001=0.12Before EDTWRD, Value of STIME= 1:12:12After EDTWRD, Value of STIME=01:12:12A zero stops zero suppression.We place it in the farthest right position where zero suppression is to stop. Thats why here the time is not suppressed at the leftmost position.67. Explain FLDCSRPRG with example.FLDCSRPRG This field-level keyword is used to define the field to which the cursor moves when exiting this field.INDARAThis keyword is used at file level.It is used to put the field option indicators and function(response) key indicators in a separate area of memory called indicator area.By using this keyword, we can make indicator data structure in our program to give the customized name to indicators defined in the display file. Hence, it makes the program more readable and easy to understand.OVERLAY This display file keyword is used at record level to specify that the record is displayed on the screen without completely erasing the previous displayed screen. Suppose we have 3 records on the display screen: HEADER, DETAIL and FOOTER, Where HEADER contains the content/data of the top part of the screen; DETAIL contains the content of data part and FOOTER contains the content of FOOTER part. Now if we want to write all the screens at the same time and want to display the content that it is containing then we go for overlay keyword. We put overlay keyword on the DETAIL and FOOTER and do the operation SFLCSRRRN This keyword is used at record level to provide the relative record number (RRN) of the record on which cursor is placed.SFLDROP This keyword is used at record level to display the subfile in truncated form i.e. the subfile records are truncated to fit on one display line. We assign a CA (command attention) or CF (command function) key to control the truncated and folded behavior of subfile by pressing the function key. By default the display mode be truncated one but when the user presses the function key it goes to folded mode. The operator presses the specified CF or CA key to switch from truncated form to folded form or from folded form to truncated form. It is used along with the keyword SFLMODE and SFLFOLD.SFLFOLD This keyword is used at record level to display the subfile in folded form by default. We assign a CA (command attention) or CF (command function) key to control the truncated and folded behavior of subfile by pressing the function key. By default the display mode is folded one but when the user presses the function key it goes to truncated mode. The operator presses the specified CF or CA key to switch from folded form to truncated form or from truncated form to folded form. It is used along with the keyword SFLMODE and SFLDROP.SFLMODE This keyword is used at record level to set the mode of the subfile i.e. to control if the subfile is to be displayed in folded or truncated form. We use a hidden variable as a parameter of this keyword to control the behavior of the subfile by setting the value of the hidden variable. The operator presses the specified CF or CA key to switch from truncated form to folded form or from folded form to truncated form. By default the display mode be truncated one. It is used along with the keyword SFLDROP and SFLFOLD.SFLINZ and SFLRNA These two keyword is used to initialize a subfile which is done in case we want to make a data entry screen. After the entry is made to be the subfile then only it becomes active, before that it will be inactive. This is done by SFLRNA. By using SFLINZ, the fields in each subfile record are initialized like as below: Session or device error Below are the situations which can lead to session or device error: Incorrect record number in subfile SFLRCDNBR or SFLSIZ field. In program code, at display (EXFMT) subfile code, check the value of RRN. If is zero and you are making on the SFLDSP indicator *ON or it is un-conditional and doing display subfile. Then it will give you the same error. Trying to show empty subfile. Field and position in Display file DDS is not correct. The keywords are not properly organized in Display file DDS. Trying to write more than 9999 record on the Display file for Load All subfile Subfile A subfile is nothing but just displaying records in tabular format on a display device. It can be an editable tabular format due to which it can be used in data entry screen, inquiry(static) screen or combination of both i.e. editing the information for a particular inquiry. The subfile first of all loads the data in subfile buffer. Maximum of 9999 can be loaded in subfile buffer at a time. Trying to load more leads to session or device error. To create a subfile we use SCREEN DSIGN AID tool (Command STRSDA) A subfile has two record format:1. Subfile control record format2. Subfile record format A subfiles process can be divided mainly into 3 parts:1. Clearing the subfile control record format.2. Loading the subfile buffer with the relevant data.3. Displaying the data from subfile buffer to the display device. CHAIN, READC, UPDATE, or WRITE operation codes can be used for subfile record format to transfer data between the program and the subfile. READ, WRITE, or EXFMT operation codes cane be used for subfile control-record format to transfer data between the program. EXFMT first of all write the keyboard input to the screen (to the screen field variable) and then read it. Hence by write operation we can have the value in the screen field available. Session or device error comes when there are no records in the database to fill the subfile. For more information on session or device error refer the chapter on Session or device error.Types of subfileI. Load-All Subfile In Load-All subfile all the records are written to the subfile buffer at once and then the data in the subfile loaded from the buffer. In this case SFLSIZ should be at-least 1 greater than the SFLPAG. If we are writing more records in the subfile buffer than the SFLSIZ declared and SFLSIZ 0 then next sentence end if display 'line 1' display 'line 2'. display 'line 3'. *** Note- there is a dot (.) only at the end of the last 2 statements, see the effect by replacing Next Sentence with Continue *** Q26) What does EXIT do ?A26) Does nothing ! If used, must be the only sentence within a paragraph.Q27) Can I redefine an X(100) field with a field of X(200)?A27) Yes. Redefines just causes both fields to start at the same location. For example:01 WS-TOP PIC X(1)01 WS-TOP-RED REDEFINES WS-TOP PIC X(2).If you MOVE '12' to WS-TOP-RED, DISPLAY WS-TOP will show 1 while DISPLAY WS-TOP-RED will show 12. A28) Can I redefine an X(200) field with a field of X(100) ?Q31)1 Yes.Q31)2 What do you do to resolve SOC-7 error? - GSQ31) Basically you need to correcting the offending data. Many times the reason for SOC7 is an un-initialized numeric item. Examine that possibility first. Many installations provide you a dump for run time abends ( it can be generated also by calling some subroutines or OS services thru assembly language). These dumps provide the offset of the last instruction at which the abend occurred. Examine the compilation output XREF listing to get the verb and the line number of the source code at this offset. Then you can look at the source code to find the bug. To get capture the runtime dumps, you will have to define some datasets (SYSABOUT etc ) in the JCL. If none of these are helpful, use judgement and DISPLAY to localize the source of error. Some installation might have batch program debugging tools. Use them.Q32) How is sign stored in Packed Decimal fields and Zoned Decimal fields?Q32) Packed Decimal fields: Sign is stored as a hex value in the last nibble (4 bits ) of the storage.Zoned Decimal fields: As a default, sign is over punched with the numeric value stored in the last bite.Q33) How is sign stored in a comp-3 field? - GSQ33) It is stored in the last nibble. For example if your number is +100, it stores hex 0C in the last byte, hex 1C if your number is 101, hex 2C if your number is 102, hex 1D if the number is -101, hex 2D if the number is -102 etc... Q34) How is sign stored in a COMP field ? - GSQ34) In the most significant bit. Bit is ON if -ve, OFF if +ve.Q35) What is the difference between COMP & COMP-3 ?Q35) COMP is a binary storage format while COMP-3 is packed decimal format.Q36) What is COMP-1? COMP-2?Q36) COMP-1 - Single precision floating point. Uses 4 bytes.COMP-2 - Double precision floating point. Uses 8 bytes.Q37) How do you define a variable of COMP-1? COMP-2?Q37) No picture clause to be given. Example 01 WS-VAR USAGE COMP-1.Q38) How many bytes does a S9(7) COMP-3 field occupy ?Q38) Will take 4 bytes. Sign is stored as hex value in the last nibble. General formula is INT((n/2) + 1)), where n=7 in this example.Q39) How many bytes does a S9(7) SIGN TRAILING SEPARATE field occupy ?Q39) Will occupy 8 bytes (one extra byte for sign).Q40) How many bytes will a S9(8) COMP field occupy ?Q40) 4 bytes. Q41) What is the maximum value that can be stored in S9(8) COMP?Q41) 99999999Q42) What is COMP SYNC?Q42) Causes the item to be aligned on natural boundaries. Can be SYNCHRONIZED LEFT or RIGHT. For binary data items, the address resolution is faster if they are located at word boundaries in the memory. For example, on main frame the memory word size is 4 bytes. This means that each word will start from an address divisible by 4. If my first variable is x(3) and next one is s9(4) comp, then if you do not specify the SYNC clause, S9(4) COMP will start from byte 3 ( assuming that it starts from 0 ). If you specify SYNC, then the binary data item will start from address 4. You might see some wastage of memory, but the access to this computational field is faster. Q43) What is the maximum size of a 01 level item in COBOL I? in COBOL II?Q43) In COBOL II: 16777215Q44) How do you reference the following file formats from COBOL programs:Q44) Fixed Block File - Use ORGANISATION IS SEQUENTIAL. Use RECORDING MODE IS F, BLOCK CONTAINS 0 .Fixed Unblocked - Use ORGANISATION IS SEQUENTIAL. Use RECORDING MODE IS F, do not use BLOCK CONTAINSVariable Block File - Use ORGANISATION IS SEQUENTIAL. Use RECORDING MODE IS V, BLOCK CONTAINS 0. Do not code the 4 bytes for record length in FD ie JCL rec length will be max rec length in pgm + 4Variable Unblocked - Use ORGANISATION IS SEQUENTIAL. Use RECORDING MODE IS V, do not use BLOCK CONTAINS. Do not code 4 bytes for record length in FD ie JCL rec length will be max rec length in pgm + 4.ESDS VSAM file - Use ORGANISATION IS SEQUENTIAL. KSDS VSAM file - Use ORGANISATION IS INDEXED, RECORD KEY IS, ALTERNATE RECORD KEY IS RRDS File - Use ORGANISATION IS RELATIVE, RELATIVE KEY ISPrinter File - Use ORGANISATION IS SEQUENTIAL. Use RECORDING MODE IS F, BLOCK CONTAINS 0. (Use RECFM=FBA in JCL DCB).Q45) What are different file OPEN modes available in COBOL?Q45) Open for INPUT, OUTPUT, I-O, EXTEND.Q46) What is the mode in which you will OPEN a file for writing? - GSQ46) OUTPUT, EXTENDQ47) In the JCL, how do you define the files referred to in a subroutine ?Q47) Supply the DD cards just as you would for files referred to in the main program. Q48) Can you REWRITE a record in an ESDS file? Can you DELETE a record from it?Q48) Can rewrite (record length must be same), but not delete.Q49) What is file status 92? - GSQ49) Logic error. e.g., a file is opened for input and an attempt is made to write to it.Q50) What is file status 39 ?Q50) Mismatch in LRECL or BLOCKSIZE or RECFM between your COBOL pgm & the JCL (or the dataset label). You will get file status 39 on an OPEN.Q51) What is Static and Dynamic linking ?Q51) In static linking, the called subroutine is link-edited into the calling program , while in dynamic linking, the subroutine & the main program will exist as separate load modules. You choose static/dynamic linking by choosing either the DYNAM or NODYNAM link edit option. (Even if you choose NODYNAM, a CALL identifier (as opposed to a CALL literal), will translate to a DYNAMIC call).A statically called subroutine will not be in its initial state the next time it is called unless you explicitly use INITIAL or you do a CANCEL. A dynamically called routine will always be in its initial state.Q52) What is AMODE(24), AMODE(31), RMODE(24) and RMODE(ANY)? (applicable to only MVS/ESA Enterprise Server).Q52) These are compile/link edit options. Basically AMODE stands for Addressing mode and RMODE for Residency mode.AMODE(24) - 24 bit addressing;AMODE(31) - 31 bit addressing AMODE(ANY) - Either 24 bit or 31 bit addressing depending on RMODE.RMODE(24) - Resides in virtual storage below 16 Meg line. Use this for 31 bit programs that call 24 bit programs. (OS/VS Cobol pgms use 24 bit addresses only).RMODE(ANY) - Can reside above or below 16 Meg line.Q53) What compiler option would you use for dynamic linking?Q53) DYNAM.Q54) What is SSRANGE, NOSSRANGE ?Q54) These are compiler options with respect to subscript out of range checking. NOSSRANGE is the default and if chosen, no run time error will be flagged if your index or subscript goes out of the permissible range.Q55) How do you set a return code to the JCL from a COBOL program?Q55) Move a value to RETURN-CODE register. RETURN-CODE should not be declared in your program.Q56) How can you submit a job from COBOL programs?Q56) Write JCL cards to a dataset with //xxxxxxx SYSOUT= (A,INTRDR) where 'A' is output class, and dataset should be opened for output in the program. Define a 80 byte record layout for the file.Q57) What are the differences between OS VS COBOL and VS COBOL II?Q57) OS/VS Cobol pgms can only run in 24 bit addressing mode, VS Cobol II pgms can run either in 24 bit or 31 bit addressing modes.I. Report writer is supported only in OS/VS Cobol.II. USAGE IS POINTER is supported only in VS COBOL II.III. Reference modification e.g.: WS-VAR(1:2) is supported only in VS COBOL II.IV. EVALUATE is supported only in VS COBOL II.V. Scope terminators are supported only in VS COBOL II.VI. OS/VS Cobol follows ANSI 74 stds while VS COBOL II follows ANSI 85 stds.VII. Under CICS Calls between VS COBOL II programs are supported.Q58) What are the steps you go through while creating a COBOL program executable?Q58) DB2 precompiler (if embedded SQL used), CICS translator (if CICS pgm), Cobol compiler, Link editor. If DB2 program, create plan by binding the DBRMs.Q59) Can you call an OS VS COBOL pgm from a VS COBOL II pgm ?Q59) In non-CICS environment, it is possible. In CICS, this is not possible.Q60) What are the differences between COBOL and COBOL II? A60) There are at least five differences: COBOL II supports structured programming by using in line Performs and explicit scope terminators, It introduces new features (EVALUATE, SET. TO TRUE, CALL. BY CONTEXT, etc) It permits programs to be loaded and addressed above the 16-megabyte line It does not support many old features (READY TRACE, REPORT-WRITER, ISAM, Etc.), and It offers enhanced CICS support. Q61) What is an explicit scope terminator? A61) A scope terminator brackets its preceding verb, e.g. IF .. END-IF, so that all statements between the verb and its scope terminator are grouped together. Other common COBOL II verbs are READ, PERFORM, EVALUATE, SEARCH and STRING. Q62) What is an in line PERFORM? When would you use it? Anything else to say about it? A62) The PERFORM and END-PERFORM statements bracket all COBOL II statements between them. The COBOL equivalent is to PERFORM or PERFORM THRU a paragraph. In line PERFORMs work as long as there are no internal GO TOs, not even to an exit. The in line PERFORM for readability should not exceed a page length - often it will reference other PERFORM paragraphs. Q63) What is the difference between NEXT SENTENCE and CONTINUE? A63) NEXT SENTENCE gives control to the verb following the next period. CONTINUE gives control to the next verb after the explicit scope terminator. (This is not one of COBOL II's finer implementations). It's safest to use CONTINUE rather than NEXT SENTENCE in COBOL II. Q64) What COBOL construct is the COBOL II EVALUATE meant to replace? A64) EVALUATE can be used in place of the nested IF THEN ELSE statements. Q65) What is the significance of 'above the line' and 'below the line'? A65) Before IBM introduced MVS/XA architecture in the 1980's a program's virtual storage was limited to 16 megs. Programs compiled with a 24 bit mode can only address 16 Mb of space, as though they were kept under an imaginary storage line. With COBOL II a program compiled with a 31 bit mode can be 'above the 16 Mb line. (This 'below the line', 'above the line' imagery confuses most mainframe programmers, who tend to be a literal minded group.) Q66) What was removed from COBOL in the COBOL II implementation? A66) Partial list: REMARKS, NOMINAL KEY, PAGE-COUNTER, CURRENT-DAY, TIME-OF-DAY, STATE, FLOW, COUNT, EXAMINE, EXHIBIT, READY TRACE and RESET TRACE. Q67) Explain call by context by comparing it to other calls. A67) The parameters passed in a call by context are protected from modification by the called program. In a normal call they are able to be modified. Q68) What is the linkage section? A68) The linkage section is part of a called program that 'links' or maps to data items in the calling program's working storage. It is the part of the called program where these share items are defined. Q69) What is the difference between a subscript and an index in a table definition? A69) A subscript is a working storage data definition item, typically a PIC (999) where a value must be moved to the subscript and then incremented or decrements by ADD TO and SUBTRACT FROM statements. An index is a register item that exists outside the program's working storage. You SET an index to a value and SET it UP BY value and DOWN BY value. Q70) If you were passing a table via linkage, which is preferable - a subscript or an index? A70) Wake up - you haven't been paying attention! It's not possible to pass an index via linkage. The index is not part of the calling programs working storage. Those of us who've made this mistake, appreciate the lesson more than others. Q71) Explain the difference between an internal and an external sort, the pros and cons, internal sort syntax etc. A71) An external sort is not COBOL; it is performed through JCL and PGM=SORT. It is understandable without any code reference. An internal sort can use two different syntaxs: 1.) USING, GIVING sorts are comparable to external sorts with no extra file processing; 2) INPUT PROCEDURE, OUTPUT PROCEDURE sorts allow for data manipulation before and/or after the sort. Q72) What is the difference between comp and comp-3 usage? Explain other COBOL usages. A72) Comp is a binary usage, while comp-3 indicates packed decimal. The other common usages are binary and display. Display is the default. Q73) When is a scope terminator mandatory? A73) Scope terminators are mandatory for in-line PERFORMS and EVALUATE statements. For readability, it's recommended coding practice to always make scope terminators explicit. Q74) In a COBOL II PERFORM statement, when is the conditional tested, before or after the perform execution? A74) In COBOL II the optional clause WITH TEST BEFORE or WITH TEST AFTER can be added to all perform statements. By default the test is performed before the perform. Q75) In an EVALUTE statement is the order of the WHEN clauses significant? A75) Absolutely. Evaluation of the WHEN clauses proceeds from top to bottom and their sequence can determine results. Q76) What is the default value(s) for an INITIALIZE and what keyword allows for an override of the default. A76) INITIALIZE moves spaces to alphabetic fields and zeros to alphanumeric fields. The REPLACING option can be used to override these defaults. Q77) What is SET TO TRUE all about, anyway? A77) In COBOL II the 88 levels can be set rather than moving their associated values to the related data item. (Web note: This change is not one of COBOL II's better specifications.) Q78) What is LENGTH in COBOL II? A78) LENGTH acts like a special register to tell the length of a group or elementary item. Q79) What is the difference between a binary search and a sequential search? What are the pertinent COBOL commands? A79) In a binary search the table element key values must be in ascending or descending sequence. The table is 'halved' to search for equal to, greater than or less than conditions until the element is found. In a sequential search the table is searched from top to bottom, so (ironically) the elements do not have to be in a specific sequence. The binary search is much faster for larger tables, while sequential works well with smaller ones. SEARCH ALL is used for binary searches; SEARCH for sequential. Q80) What is the point of the REPLACING option of a copy statement? A80) REPLACING allows for the same copy to be used more than once in the same code by changing the replace value. Q81) What will happen if you code GO BACK instead of STOP RUN in a stand alone COBOL program i.e. a program which is not calling any other program.A81) The program will go in an infinite loop.Q82) How can I tell if a module is being called DYNAMICALLY or STATICALLY?A82) The ONLY way is to look at the output of the linkage editor (IEWL)or the load module itself. If the module is being called DYNAMICALLY then it will not exist in the main module, if it is being called STATICALLY then it will be seen in the load module. Calling a working storage variable, containing a program name, does not make a DYNAMIC call. This type of calling is known as IMPLICITE calling as the name of the module is implied by the contents of the working storage variable. Calling a program name literal (CALL Q83) What is the difference between a DYNAMIC and STATIC call in COBOL.A83) To correct an earlier answer: All called modules cannot run standalone if they require program variables passed to them via the LINKAGE section. DYNAMICally called modules are those that are not bound with the calling program at link edit time (IEWL for IBM) and so are loaded from the program library (joblib or steplib) associated with the job. For DYNAMIC calling of a module the DYNAM compiler option must be chosen, else the linkage editor will not generate an executable as it will expect u address resolution of all called modules. A STATICally called module is one that is bound with the calling module at link edit, and therefore becomes part of the executable load module. Q84) How may divisions are there in JCL-COBOL?A84) SIXQ85) What is the purpose of Identification Division?A85) Documentation.Q86) What is the difference between PIC 9.99 and 9v99?A86) PIC 9.99 is a FOUR-POSITION field that actually contains a decimal point where as PIC 9v99 is THREE- POSITION numeric field with implied or assumed decimal position.Q87) what is Pic 9v99 Indicates? A87) PICTURE 9v99 is a three position Numeric field with an implied or assumed decimal point after the first position; the v means an implied decimal point.Q88) What guidelines should be followed to write a structured Cobol prg'm?A88) 1) use 'evaluate' stmt for constructing cases. 2) use scope terminators for nesting. 3) use in line perform stmt for writing 'do ' constructions. 4) use test before and test after in the perform stmt for writing do-while constructions. Q89) Read the following code. 01 ws-n pic 9(2) value zero. a-para move 5 to ws-n. perform b-para ws-n times. b-para. move 10 to ws-n. how many times will b-para be executed ?A89) 5 times only. it will not take the value 10 that is initialized in the loop.Q90) What is the difference between SEARCH and SEARCH ALL? What is more efficient?A90) SEARCH is a sequential search from the beginning of the table. SEARCH ALL is a binary search, continually dividing the table in two halves until a match is found. SEARCH ALL is more efficient for tables larger than 70 items. Q91) What are some examples of command terminators?A91) END-IF, END-EVALUATEQ92) What care has to be taken to force program to execute above 16 Meg line?A92) Make sure that link option is AMODE=31 and RMODE=ANY. Compile option should never have SIZE(MAX). BUFSIZE can be 2K, efficient enough.Q93) How do you submit JCL via a Cobol program?A93) Use a file //dd1 DD sysout=(*, intrdr)write your JCL to this file. Pl some on try this out.Q94) How to execute a set of JCL statements from a COBOL programA94) Using EXEC CICS SPOOL WRITE(var-name) END-EXEC command. var-name is a COBOL host structure containing JCL statements.Q95) Give some advantages of REDEFINES clause.A95) 1. You can REDEFINE a Variable from one PICTURE class to another PICTURE class by using the same memory location.2. By REDEFINES we can INITIALISE the variable in WORKING-STORAGE Section itself.3. We can REDEFINE a Single Variable into so many sub variables. (This facility is very useful in solving Y2000 Problem.) Q96) What is the difference between static call & Dynamic callA96) In the case of Static call, the called program is a stand-alone program, it is an executable program. During run time we can call it in our called program. As about Dynamic call, the called program is not an executable program it can executed through the called program Q97) What do you feel makes a good program?A97) A program that follows a top down approach. It is also one that other programmers or users can follow logically and is easy to read and understand.Q98) How do you code Cobol to access a parameter that has been defined in JCL? And do you code the PARM parameter on the EXEC line in JCL?A98) 1) using JCL with sysin. //sysin dd *here u code the parameters(value) to pass in to cobol program /* and in program you use accept variable name(one accept will read one row)/.another way.2) in jcl using parm statement ex: in exec statement parm='john','david' in cobol pgm u have to code linkage section in that for first value you code length variable and variable name say, abc pic x(4).it will take john inside to read next value u have to code another variable in the same way above mentioned.Q99) Why do we code S9(4) comp. Inspite of knowing comp-3 will occupy less space.A99) Here s9(4)comp is small integer ,so two words equal to 1 byte so totally it will occupy 2 bytes(4 words).here in s9(4) comp-3 as one word is equal to 1/2 byte.4 words equal to 2 bytes and sign will occupy 1/2 byte so totally it will occupy 3 bytes.Q100) The maximum number of dimensions that an array can have in COBOL-85 is ----------- ?A100) SEVEN in COBOL - 85 and THREE in COBOL - 84Q101) How do you declare a host variable (in COBOL) for an attribute named Emp-Name of type VARCHAR(25) ?A101) 01 EMP-GRP. 49 E-LEN PIC S9(4) COMP. 49 E-NAME PIC X(25).Q102) What is Comm?A102) COMM - HALF WORD BINARYQ103) Differentiate COBOL and COBOL-II. (Most of our programs are written in COBOLII, so, it is good to know, how, this is different from COBOL) A103) The following features are available with VS COBOL II: 1. MVS/XA and MVS/ESA support The compiler and the object programs it produces can be run in either 24- or 31-bit addressing mode. 2. VM/XA and VM/ESA support The compiler and the object programs it produces can be run in either 24- or 31-bit addressing mode. 3. VSE/ESA support The compiler and the object programs it produces can be run under VSE/ESA. Q104) What is PERFORM ? What is VARYING ? (More details about these clauses) A104) The PERFORM statement is a PROCEDURE DIVISION statement which transfers control to one or more specified procedures and controls as specified the number of times the procedures are executed. After execution of the specified procedures is completed (i.e., for the appropriate number of times or until some specified condition is met), control is transferred to the next executable statement following the PERFORM statement. There are 5 types of PERFORM statements: a) Basic PERFORM b) PERFORM TIMES c) PERFORM UNTIL d) PERFORM VARYINGe) IN-LINE PERFORM Q105) How many sections are there in data division?. A105) SIX SECTIONS 1.FILE SECTION 2.WORKING-STORAGE SECTION 3. LOCAL-STORAGE SECTION 4.SCREEN SECTION 5.REPORT SECTION 6. LINKAGE SECTIONQ106) What is Redefines clause?A106) Redefines clause is used to allow the same storage allocation to be referenced by different data names . Q107) How many bytes does a s9(4)comp-3 field occupy?A107) 3Bytes (formula : n/2 + 1))Q108) What is the different between index and subscript?A108) Subscript refers to the array of occurrence , where as Index represents an occurrence of a table element. An index can only modified using perform, search & set. Need to have an index for a table in order to use SEARCH and SEARCH All.Q109) What is the difference between Structured COBOL Programming and Object Oriented COBOL programming?A109) Structured programming is a Logical way of programming, you divide the functionalities into modules and code logically. OOP is a Natural way of programming; you identify the objects first, and then write functions, procedures around the objects. Sorry, this may not be an adequate answer, but they are two different programming paradigms, which is difficult to put in a sentence or two.Q110) What divisions, sections and paragraphs are mandatory for a COBOL program?A110) IDENTIFICATION DIVISION and PROGRAM-ID paragraph are mandatory for a compilation error free COBOL program.Q111) Can JUSTIFIED be used for all the data types?A111) No, it can be used only with alphabetic and alphanumeric data types.Q112) What happens when we move a comp-3 field to an edited (say z (9). ZZ-) A112) the editing characters r to be used with data items with usage clause as display which is the default. When u tries displaying a data item with usage as computational it does not give the desired display format because the data item is stored as packed decimal. So if u want this particular data item to be edited u have to move it into a data item whose usage is display and then have that particular data item edited in the format desired.Q113) What will happen if you code GO BACK instead of STOP RUN in a stand-alone COBOL program i.e. a program which is not calling any other program ?A113) Both give the same results when a program is not calling any other program. GO BACK will give the control to the system even though it is a single program.Q114) what is the difference between external and global variables?A114) Global variables are accessible only to the batch program whereas external variables can be referenced from any batch program residing in the same system library.Q115) You are writing report program with 4 levels of totals: city, state, region and country. The codes being used can be the same over the different levels, meaning a city code of 01 can be in any number of states, and the same applies to state and region code so how do you do your checking for breaks and how do you do add to each level?A115) Always compare on the highest-level first, because if you have a break at a highest level, each level beneath it must also break. Add to the lowest level for each record but add to the higher level only on a break.Q116) What is difference between COBOL and VS COBOL II?.A116) In using COBOL on PC we have only flat files and the programs can access only limited storage, whereas in VS COBOL II on M/F the programs can access up to 16MB or 2GB depending on the addressing and can use VSAM files to make I/O operations faster.Q117) Why occurs can not be used in 01 level ?A117) Because, Occurs clause is there to repeat fields with same format, not the records.Q118) What is report-item?A118) A Report-Item Is A Field To Be Printed That Contains Edit SymbolsQ119) Difference between next and continue clauseA119) The difference between the next and continue verb is that in the continue verb it is used for a situation where there in no EOF condition that is the records are to be accessed again and again in an file, whereas in the next verb the indexed file is accessed sequentially, read next record command is used. Q120) What is the Importance of GLOBAL clause According to new standards of COBOLA120) When any data name, file-name, Record-name, condition name or Index defined in an Including Program can be referenced by a directly or indirectly in an included program, Provided the said name has been declared to be a global name by GLOBAL Format of Global Clause is01 data-1 pic 9(5) IS GLOBAL.Q121) What is the Purpose of POINTER Phrase in STRING commandA121) The Purpose of POINTER phrase is to specify the leftmost position within receiving field where the first transferred character will be storedQ122) How do we get current date from system with century?A122) By using Intrinsic function, FUNCTION CURRENT-DATEQ123) What is the maximum length of a field you can define using COMP-3?A123) 10 Bytes (S9(18) COMP-3).Q124) Why do we code s9 (4) comp? In spite of knowing comp-3 will occupy less space?A124) Here s9(4)comp is small integer, so two words equal to 1 byte so totally it will occupy 2 bytes(4 words).here in s9(4) comp-3 as one word is equal to 1/2 byte.4 words equal to 2 bytes and sign will occupy 1/2 byte so totally it will occupy 3 bytes.Q125) What is the LINKAGE SECTION used for?A125) The linkage section is used to pass data from one program to another program or to pass data from a PROC to a program.Q126) Describe the difference between subscripting and indexing ?A126) Indexing uses binary displacement. Subscripts use the value of the occurrence.