Test by Bikram | Operating Systems | Test 2 | Question: 4

Question

Consider a situation, in which several people are executing copies of a mail program. Which of the following statements is/are not correct:

1. All the users share one program counter and stack for mail program.
2. All the users share the same execution sequence.
3. All the users share same text section, but data section varies necessarily.

• A. I and II
• B. only I
• C. only II
• D. only III

Answer 1

The mail program runs as different processes for different users, so there is no sharing of program counter and stack. Each user has his own program counter and stack. This statement is false.

The execution sequence must be different for the users because each user may be doing a different task like one doing mail composing while other clearing the Thrash. This statement is False.

The statement 3 is correct because it is the same program making the text section the same. Data section gets populated by the data of a particular user and need not be same as that of another.

Comments

@ hem chandra joshi  

Read all previous comments , i post a snap see it .

And in my answer i wrote I is not correct . Only statement III is correct .

Question asks , Which of the following statements are not correct: so answer is I and II ,  which is represented by option A .

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How III is correct??..

thanks

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"nevertheless" might be confusing for someone not for all as it's confusing me while reading this statement:

Although two process may be associated with the same program, they are nevertheless considered two separate execution sequence.

$nevertheless=however$

Now it sound good:

Although two process may be associated with the same program, they are however considered two separate execution sequence. !!

Answer 2

Even if two processes are associated with the same program, they're not considered the same process.

• The execution sequence is considered different.
  (one process might take the branch, other might not etc)
   
• The heap section is considered different.
  (obviously different pieces of memory from heap allocated)
   
• The stack section is considered different.
  (different activation records could be pushed on stack)
   
• The data section is considered different.
  (static and global variables probably get assigned different values depending on dynamic factors)
   
• Only the text section is considered same.
  (Text section has the programmed code. It'll be same for different processes of the same program)

Option A

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Please do your own research on what a process and a program exactly is. (Hint: One is active, other is passive)