Operating System - Study Mode

[#451] A relationship between processes such that each has some part (critical section) which must not be executed while the critical section of another is being executed, is known as
Correct Answer

(B) mutual exclusion

Explanation

Solution: A relationship between processes such that each has some part (critical section) which must not be executed while the critical section of another is being executed, is known as mutual exclusion

[#452] What is the name of the operating system which was originally designed by scientists and engineers for use by scientists and engineers?
Correct Answer

(B) UNIX

Explanation

Solution: In 1969 a team led by computer scientists Ken Thompson and Dennis Ritchie created the first version of UNIX on a PDP-7 minicomputer, which was chosen mainly because of Thompson's familiarity with the system from his hobby work on it.

[#453] The most common security failure is
Correct Answer

(A) carelessness by users

Explanation

Solution: In security contexts, User Carelessness refers to any action taken by a user for purposes of expedience that has a negative impact on security.

[#454] Terminal Table
Correct Answer

(D) a permanent table which lists all key words and special symbols of the language in symbolic form.

Explanation

Solution: A permanent database that has entry for each terminal symbols such as arithmetic operators, keywords, punctuation characters such as etc Fields.

[#455] Block or buffer caches are used
Correct Answer

(A) to improve disk performance

Explanation

Solution: Buffer cache is where data blocks are copied to perform SQL operations. Buffer cache is shared memory structure and it is concurrently accessed by all server processes.