1. What is primary allocation for a dataset? 數據集的Primary allocation指的是什么？
The space allocated when the dataset is first created. 數據集第一次被創建的時候所分配的空間。
2. What is the difference between primary and secondary allocations for a dataset?
數據集的between primary and secondary allocations之間有什么不同？
Secondary allocation is done when more space is required than what has already been allocated.
secondary allocations是指當系統需要更多的空間的時候，數據集被新增加空間的后的增量。
3.How many extents are possible for a sequential file ? For a VSAM file ? 數據文件和VSAM文件分別最多有多少個擴展
16 extents on a volume for a sequential file and 123 for a VSAM file. 順序文件有一個卷上有16個擴展，而VSAM有123個
4. What does a disposition of (NEW,CATLG,DELETE) mean? 處置語句(NEW,CATLG,DELETE)是什么意思？
That this is a new dataset and needs to be allocated, to CATLG the dataset if the step is successful and to delete the dataset if the step abends.
意思是，這是一個新的數據集將要被分配，編目這個數據集假如作業步是成功的，刪除這個數據集假如作業步abend了。
5. What does a disposition of (NEW,CATLG,KEEP) mean? 處置語句(NEW,CATLG,KEEP)是什么意思？
That this is a new dataset and needs to be allocated, to CATLG the dataset if the step is successful and to KEEP but not CATLG the dataset if the step abends. Thus if the step abends, the dataset would not be catalogued and we would need to supply the vol. ser the next time we refer to it.
意思是，這是一個新的數據集將要被分配，編目這個數據集假如作業步是成功的，假如這個作業步不成功那就不編目了，但是作業部正常結束后，該數據集將被繼續保留在相應的卷上，然而，如果這個數據集abend了，這個數據集不應該被編目，而我們應該提供vol.ser值，在下次的引用中。
6. How do you access a file that had a disposition of KEEP? 怎么使用含有處置語句KEEP的數據集
Need to supply volume serial no. VOL=SER=xxxx. 不需要提供卷的序列號， 使用VOL=SER=xxxx
7. What does a disposition of (MOD,DELETE,DELETE) mean ? 處置語句(MOD,DELETE,DELETE)是什么意思？
The MOD will cause the dataset to be created (if it does not exist), and then the two DELETEs will cause the dataset to be deleted whether the step abends or not. This disposition is used to clear out a dataset at the beginning of a job.
MOD，這個數據集將會被創建假如不存在，兩個Delete將會刪除數據集無論作業步驟abend與否，這個處置語句通常是用于在作業的開始用于清理數據集
8. What is the DD statement for a output file? 如何用DD語句創建輸出文件
Unless allocated earlier, will have the foll parameters: 除非之前已經創建，可以用下面的參數來實現
DISP=(NEW,CATLG,DELETE), UNIT , SPACE & DCB .
9. What do you do if you do not want to keep all the space allocated to a dataset? 假如你不想保留那些已經分配給數據集的空間
Specify the parameter RLSE ( release ) in the SPACE e.g. 使用在SPACE語句中使用RLSE ( release )參數
SPACE=(CYL,(50,50),RLSE)
10. What is DISP=(NEW,PASS,DELETE)? 處置語句(NEW,PASS,DELETE)是什么意思？
This is a new file and create it, if the step terminates normally, pass it to the subsequent steps and if step abends, delete it. This dataset will
not exist beyond the JCL. 這是一個將要被創建的文件，假如作業步正常的結束，傳遞給子作業步，假如步驟abend了，刪除它，這個數據集將在作業步結束時刪除
11. How do you create a temporary dataset? Where will you use them?
Temporary datasets can be created either by not specifying any DSNAME or by specifying the temporary file indicator as in DSN=&&TEMP. We use them to carry the output of one step to another step in the same job. The dataset will not be retained once the job completes.
12. How do you restart a proc from a particular step? 如何在特定的作業步中重新啟動一個子程序？
In job card, specify RESTART=procstep.stepname where procstep = name of the jcl step that invoked the proc and stepname = name of the proc step where you want execution to start
13. How do you skip a particular step in a proc/JOB? 如何跳過一個特定的作業步？
Can use either condition codes or use the jcl control statement IF (only in ESA JCL)可以使用either 或者是作業控制語句IF
13a. A PROC has five steps. Step 3 has a condition code. How can you override/nullify this condition code?
一個子程序有五個作業步？作業步3含有條件編碼，你是如果覆蓋/使這個條件碼無效？
Provide the override on the EXEC stmt in the JCL as follows:在EXEC語句中提供覆蓋
//STEP001 EXEC procname,COND.stepname=value
All parameters on an EXEC stmt in the proc such as COND, PARM have to be overridden like this.
14. How do you override a specific DDNAME/SYSIN in PROC from a JCL? 如果在子程序中覆蓋一個特定DDNAME/SYSIN
//<stepname.dd> DSN=...
15. What is NOTCAT 2 ? 什么是NOTCAT 2
This is an MVS message indicating that a duplicate catalog entry exists. E.g., if you already have a dataset with dsn = xxx.yyyy; and u try to create one with disp new,catlg, you would get this error. the program open and write would go through and at the end of the step the system would try to put it in the system catalog. at this point since an entry already exists the catlg would fail and give this message. you can fix the problem by deleting/uncataloging the first data set and going to the volume where the new dataset exists(this info is in the msglog of the job) and cataloging it.
這是一個MVS信息，它表明系統已經含有一個同樣編目的數據集，例如，你已經含有一個dsn為xxx.yyyy的數據集合，但是你卻希望通過處置語句DISP來編碼，那么你就會遇到這樣錯了，系統會繼續打開和寫入這個數據集，最后，系統會嘗試對它進行編目，就在這個時候，既然一個已經存一個同名的數據集，這會導致系統fail和拋出這個消息，要修正這個文件，你可以通過刪除或者對現有的這個文件接觸編碼。
16. What is 'S0C7' abend? 什么是SC07 abend
Caused by invalid data in a numeric field. 數字字段中含有不合法的數據
17. What is a S0C4 error ? 什么是
Storage violation error - can be due to various reasons. e.g.: READING a file that is not open, invalid address referenced due to subscript error.
18. What are SD37, SB37, SE37 abends?
All indicate dataset out of space. SD37 - no secondary allocation was specified. SB37 - end of vol. and no further volumes specified. SE37 - Max. of 16 extents already allocated.
19. What is S322 abend ?
Indicates a time out abend. Your program has taken more CPU time than the default limit for the job class. Could indicate an infinite loop.
20. Why do you want to specify the REGION parameter in a JCL step?
To override the REGION defined at the JOB card level.REGION specifies the max region size. REGION=0K or 0M or omitting REGION
means no limit will be applied.
21. What does the TIME parameter signify ? What does TIME=1440 mean ?
TIME parameter can be used to overcome S322 abends for programs that genuinely need more CPU time. TIME=1440 means no CPU time limit is to be applied to this step.
22. What is COND=EVEN ?
Means execute this step even if any of the previous steps, terminated abnormally.
23. What is COND=ONLY ?
Means execute this step only if any of the previous steps, terminated abnormally.
24. How do you check the syntax of a JCL without running it?
TYPERUN=SCAN on the JOB card or use JSCAN.
25. What does IEBGENER do?
Used to copy one QSAM file to another. Source dataset should be described using SYSUT1 ddname. Destination dataset should be decribed using SYSUT2. IEBGENR can also do some reformatting of data by supplying control cards
via SYSIN.
26. How do you send the output of a COBOL program to a member of a PDS?
Code the DSN as pds(member) with a DISP of SHR. The disp applies to the pds and not to a specific member.
27. I have multiple jobs ( JCLs with several JOB cards ) in a member. What happens if I submit it?
Multiple jobs are submitted (as many jobs as the number of JOB cards).
28. I have a COBOL program that ACCEPTs some input data. How do you code
the JCL statment for this? ( How do you code instream data in a JCL? )
//SYSIN DD*
input data
input data
/*
29. Can you code instream data in a PROC ?
No.
30. How do you overcome this limitation ?
One way is to code SYSIN DD DUMMY in the PROC, and then override this from the JCL with instream data.
31. How do you run a COBOL batch program from a JCL? How do you run a COBOL/DB2 program?
To run a non DB2 program,
//STEP001 EXEC PGM=MYPROG
To run a DB2 program,
//STEP001 EXEC PGM=IKJEFT01
//SYSTSIN DD *
DSN SYSTEM(....)
RUN PROGRAM(MYPROG)
PLAN(.....) LIB(....) PARMS(...)
/*
32. What is STEPLIB, JOBLIB? What is it used for?
Specifies that the private library (or libraries) specified should be searched before the default system libraries in order to locate a program to be executed.STEPLIB applies only to the particular step, JOBLIB to all steps in the job.
33. What is order of searching of the libraries in a JCL?
First any private libraries as specified in the STEPLIB or JOBLIB, then the system libraries such as SYS1.LINKLIB. The system libraries are specified in the linklist.
34. What happens if both JOBLIB & STEPLIB is specified ?
JOBLIB is ignored.
35. When you specify mutiple datasets in a JOBLIB or STEPLIB, what factor determines the order?
The library with the largest block size should be the first one.
36. How to change default proclib ?
//ABCD JCLLIB ORDER=(ME.MYPROCLIB,SYS1.PROCLIB)
37. The disp in the JCL is MOD and the program opens the file in OUTPUT mode. What happens ?
The disp in the JCL is SHR and the pgm opens the file in EXTEND mode. What happens ?
Records will be written to end of file (append) when a WRITE is done in
both cases.
38. What are the valid DSORG values ?
PS - QSAM, PO - Partitioned, IS - ISAM
39. What are the differences between JES2 & JES3 ?
JES3 allocates datasets for all the steps before the job is scheduled. In
JES2, allocation of datasets required by a step are done only just before
the step executes.