CICS Interview questions

First of all, CICS stands for the Customer Information Control System. This type of system controls all the online transactions of the management of IBM. A CICS is a type of processing that is mainly initiated by the use of the single request that can also affect the one or more of the objects. The CICS was being founded in the year 1969.

In the CICS, PPT mainly stands for the Processing Programming Table. The PPT contains details like a program’s name, Mapset names, task use counter, language, size, main storage address etc.

The following are some of the main uses of PPT in CICS and they are:

1. All the CICS and the programs are to be registered in the Processing Programming Table.
2. A Program Control Program or PCP is a type of program that mainly refers to the PPT.
3. It’s really very much compulsory that you have to register the program here. If it’s not been registered then the CICS will also not recognize it.

The following are some of the important programs that are used in the CICS:

• TCP
• KCP
• PCP
• FCP
• SCP

TCP basically stands for the Terminal Control Program. TCP is used to receive all the messages from the terminals and also used to request the CISC to initiate or start the task.

Firstly, KCP stands for the Task Control program. KCP generally is used to control all the execution task and their related properties. Apart from this, it also helps to handle all the issues that are mainly related to multitasking.

The PCP stands for the Program Control Program. PCP is mainly used for locating and load the program for the execution. The main working of the PCP is it just transfer the control between the programs and in the end, it returns the control back to CICS.

The following are some of the main uses of the transaction in the CICS:

• A transaction is a unique identifier that is mainly used to execute or start a particular task.
• A transaction is the type of the four characters entry and there will be no duplicates allowed particularly in the transaction names.
• A transaction can be triggered concurrently from the different systems but not from the same systems.
• A transaction will mainly have one to one or many mappings to the program that basically needs to be executed when the transaction trigger is taken place.

FCT stands for the File Control Table. All the types of the VSAM files used in the CICS programs have to be registered in the file control table. FCP is a type of program that mainly refers to the FCT. The FCT has ACCMETH or the data access method, DATASET or the Dataset name, File ( file name), SERVEQ or the operation needs to be performed on, FILESTAT or the file initial status, BUFND or the number of the data numbers and BUFNI or the numbers of index buffers.

BMS stands for the Basic Mapping Support. BMS is being provided by the CICS. The BMS will always help to define and format the screen. When you are going to define a screen by using the BMS then the screen is called the MAP. The collections of all the screen are called as the Mapset.

The following are the types of 3 processes in which the MAP in CICS is being created :

• DFHMDF: This helps to design an individual field on the screen or the page.
• DFHMDI: It helps to define a single map in the collections of the field.
• DFHMSD: It helps to group a single map into a map set.

The following are some of the types of the DFHMDF present in the CICS set:

• POS: POS stands for the position in the CICS. The POS parameter helps to indicate the row and column position in the field that is relative to the upper left corner of the map position.
• Length: The length always indicates the characters that are present in the field. In the length, the attribute bytes are not present so each of the lengths will occupy one more column as compared to its length value.
• ATTRB: ATTRB stands for the field attribute. Usually, the field attribute is not required in the BMS. This is because the BMS always uses the default value of the auto-skip protection, normal intensity and the modified tag on.
• Initial: Initial is also not needed in the BMS. You can only use the initial in the label and the title field that already has a constant value in the BMS.
• Picout: Picout is one of the definitions of the filed CHG. It helps to tell the BMS that what types of pictures is mainly used to generate the fields. The Picout will also help you edit the facilities of the COBOL or the PL/I as you move the data into the map.
• GRPNAME and OCCURS: GRPNAME and OCCURS options always do not appear in the simple example, because they are one of the most complex forms. The GRPNAME are always used to subdivide a map field within the program for the later processing and the OCCURS will mainly help you to define adjacent.

The following are some of the classifications of the CICS:

• Non Conventional programs
• Conversational programs
• Pseudo conversational programs

While you are using the non-conventional programs then the human intervention is not at all required. The Non-conventional programs are just similar to the batch program and also run in the batch mode. They are just used for displaying a sequence on the screen at the regular interval of time.

A conversational program is mainly used to send a message to the terminals and receiving a response from the active users. The online application always uses the conversation between the users and the application program by the use of the send and receive command.