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Correct ANSWER is (d) 3

The best I can explain: There are three distinct phases of a PROCESS which uses three different SYSTEM calls or functions. A process can be in its initial state when it is created, after that, the process is in execution state when the INSTRUCTIONS of a process are being executed. The third phase of a process is waiting for state when the process is waiting for some action to be taken.

The correct answer is (B) -u

For EXPLANATION I WOULD say: The system ADMINISTRATOR needs to use the -u (user) OPTION to know the activities of a user. For example,

Right OPTION is (d) size

To EXPLAIN I would say: PS command displays the processes owned by the user RUNNING the command. If we execute the command immediately after logging in, it MAY produce an output like this:

Right answer is (c) PS

The explanation is: ps command is USED to show some ATTRIBUTES of a process. This command reads through the kernel’s data structures and process tables to fetch the characteristics of a process. By default, ps command displays the processes owned by the user RUNNING the command.

Correct answer is (d) pwd and cd

Easiest EXPLANATION: When we run a command, a process REPRESENTING the command is started by the SHELL process but all COMMANDS don’t SET up processes. Built-in commands of the shell like pwd, cd etc do not create processes.

The CORRECT choice is (a) shell

The BEST explanation: As we log on to a UNIX system, a process is immediately set up by the kernel. This process REPRESENTS a UNIX command which may sh (Bourne shell), ksh (Korn shell), CSH (C shell) or bash (Bash). This process remains alive until we log out when it is killed by the kernel.

Correct ANSWER is (B) 0

To explain: EVERY process has a parent process, we can’t have any orphaned process for a longer time. The ancestry of every process is ultimately traced to the first process (PID 0) that is set up when the system is booted. It’s LIKE the root DIRECTORY of the system.

Right option is (b) False

The BEST explanation: The PID of our LOGIN shell can’t obviously change as LONG as we are logged in. But when we log out and log in again, our login shell will be assigned a different PID. This knowledge of PID is necessary to CONTROL the activities at our terminal.

The CORRECT ANSWER is (a) ECHO $$

To explain: The shell’s pathname is stored in SHELL, but it’s PID is stored in a SPECIAL variable, $$. To know the PID of our current shell, type

Correct option is (c) PROCESS table

To explain: As every process has some attributes. Some of these attributes are maintained by the KERNEL in memory in a SEPARATE structure called the process table. A process table is simply an array of many pcb’s. Process table CONTAINS two MAJOR attributes of a process i.e. processed and parent process ID.

The correct option is (b) PPID

To explain I would say: The PARENT ID of a CHILD PROCESS is calledPPID (parent process ID) and is available as a process attribute. It is COMMON that several processes have the same parent. When several processes have the same parent, it often makes sense to kill the parent process RATHER than killing each child separately.

Correct option is (b) False

The best explanation: Both pcb and PROCESS table store attributes and information about processes. But the major DIFFERENCE between both is, pcb CONTAINS all the information about the process and is used in CONTEXT switching while process table contains very few attributes of a process like registers, PID, parent pid.

The correct choice is (B) executing

To elaborate: A process is simply an instance of a running program. A process PASSES through many states throughout its LIFE cycle i.e. when it is BORN until it is executed. After the process has completed it is said to be terminated.

Correct answer is (a) BORN

The best explanation: A process is said to be born when it STARTS its execution. It is the initial state of a process. The process is assigned to CPU for its execution further.

Right choice is (b) False

For explanation I WOULD say: PROGRAM should not be confused with the PROCESS. Both differ from each other but very slightly. The process is only an INSTANCE of a RUNNING program. Until a program hasn’t started its execution it is referred to a program only but as soon it is in execution state it is called as a process.

Correct option is (a) process control BLOCK (pcb)

Easy explanation: A process control block is a data structure which is used for STORING information about a process. It is also known as task control block and is MAINTAINED by the kernel for maintenance of a process. Each process has its own pcb.