文档介绍：What are the three main purposes of an operating system?
Answer:
• To provide an environment for puter user to execute programs puter hardware in a convenient and efficient manner.
• To allocate the separate resources of puter as needed to solve the problem given. The allocation process should be as fair and efficient as possible.
• As a control program it serves two major functions: (1) supervision of the execution of user programs to prevent errors and improper use of puter, and (2) management of the operation and control of I/O devices.
What are the main differences between operating systems for puters and puters?
Answer: Generally, operating systems for batch systems have simpler requirements than for puters. Batch systems do not have to be concerned with interacting with a user as much as a puter. As a result, an operating system for a PC must be concerned with response time for an interactive user. Batch systems do not have such requirements. A pure batch system also may have not to handle
time sharing, whereas an operating system must switch rapidly between different jobs.
List the four steps that are necessary to run a program on pletely dedicated machine.
Answer:
a. Reserve machine time.
b. Manually load program into memory.
c. Load starting address and begin execution.
d. Monitor and control execution of program from console.
We have stressed the need for an operating system to make efficient use of puting hardware. When is it appropriate for the operating system to forsake this principle and to “waste” resources? Why is such a system not really wasteful?
Answer: Single-user systems should maximize use of the system for the user. A GUI might “waste” CPU cycles, but it optimizes the user’s interaction with the system.
What is themain difficulty that a programmer must e in writing an operating system for a real-time environment?
Answer: The main difficulty is keeping the operating system within the fixed time constraints