Question

In the two-level directory, if a user refers to a particular file then__________________

Select one:

a. first UFD (user file directory) is searched, then MFD (master file directory)

b. only his/her own UFD (user file directory) is searched

（WRONG）c. first MFD (master file directory) is searched, then UFD (user file directory)

d. only MFD (master file directory) is searched

When the exclusive lock is applied to a file then _____________

Select one:

a. many processes can read and write to this file concurrently

b. only one process can write to this file, but many processes can read it concurrently

c. processes can write to this file only

d. only one process can use this file

Which of these RAID levels is best for storing large volumes of data?

Select one:

a. RAID level 3

b.

RAID levels 0 + 1 and 1 + 0

c. RAID level 4

d. RAID level 5

Answer 1

1) In the two-level directory, if a user refers to a particular file

Answer: b. only his/her own UFD (user file directory) is searched

• In the two-level directory structure, each user has his own user file directory (UFD). The UFDs have similar structures, but each lists only the files of a single user.
• When a user job starts or a user logs in, the system's master file directory (MFD) is searched.
• It cannot be "first UFD (user file directory) is searched, then MFD (master file directory)" and "first MFD (master file directory) is searched, then UFD (user file directory)" since only UFD is searched in two level directory.
• In two level directorey when a user job starts or a user logs in, the system's master file directory (MFD) is searched. So it cannot be the answer.

The answer is 100% correct. I was not sure about the parts so I didn't answer them.

Please let me know if you have any doubts on the first part.