UNIX

Question 1

Match the following WINDOWS system calls and UNIX system calls with reference to process control and File manipulation.

• (1)
• (2)
• (3)
• (4)

Question 2

The Unix Operating System Kernel maintains two key data structures related to processes, the process table and the user structure. Now, consider the following two statements : I. The process table is resident all the time and contain information needed for all processes, even those that are not currently in memory. II. The user structure is swapped or paged out when its associated process is not in memory, in order not to waste memory on information that is not needed. Which of the following options is correct with reference to above statements ?

• Only (I) is correct.
• Only (II) is correct.
• Both (I) and (II) are correct.
• Both (I) and (II) are wrong.

Question 3

In UNIX, processes that have finished execution but have not yet had their status collected are known as _________.

• Sleeping processes
• Stopped processes
• Zombie processes
• Orphan processes

Question 4

What is the function of following UNIX command ?

WC – l <a  >b&

• It runs the word count program to count the number of lines in its input, a, writing the result to b, as a foreground process.
• It runs the word count program to count the number of lines in its input, a, writing the result to b, but does it in the background.
• It counts the errors during the execution of a process, a, and puts the result in process b.
• It copies the ‘l’ numbers of lines of program from file, a, and stores in file b.

Question 5

In Unix, the login prompt can be changed by changing the contents of the file __________.

• crontab

• init

• gettydefs

• inittab

Question 6

Match the following in Unix file system:

• (1)
• (2)
• (3)
• (4)

Question 7

What will be the output of the following Unix command ? $rm chap0\\[1 - 3\\]

• Remove file chap0[1 - 3]
• Remove file chap01, chap02, chap03
• Remove file chap\\[1 - 3\\]
• None of the above

Question 8

Match the following for unix system calls : List - I List - II (a) exec (i) Creates a new process (b) brk (ii) Invokes another program overlaying memory space with a copy of an executable file (c) wait (iii) To increase or decrease the size of data region (d) fork (iv) A process synchronizes with termination of child process Codes : (a) (b) (c) (d) (1) (ii) (iii) (iv) (i) (2) (iii) (ii) (iv) (i) (3) (iv) (iii) (ii) (i) (4) (iv) (iii) (i) (ii)

• (1)
• (2)
• (3)
• (4)

Question 9

The unix command: $ vi file1 file2

• Edits file1 and stores the contents of file1 in file2
• Both files i.e. file1 and file2 can be edited using \'ex\' command to travel between the files
• Both files can be edited using \'mv\' command to move between the files
• Edits file1 first, saves it and then edits file2

Question 10

The difference between a named pipe and a regular file in Unix is that

• Unlike a regular file, named pipe is a special file
• The data in a pipe is transient, unlike the content of a regular file
• Pipes forbid random accessing, while regular files do allow this.
• All of the above