OSG202
_____ are used to model printers, modems, and other devices that accept or output a
character stream
a. A character special file
b. A separate special file
c. A block special file
d. A pipe special file - ✔️✔️a
Which of these statements about Monolithic Systems are true?
a. A set of service procedures that carry out the system calls
b. A set of utility procedures that Help the service procedures
c. A main program that invokes the requested service procedure
d. All of others - ✔️✔️a
Which is the difference between personal computers and mainframe computers?
a. Personal computers are always interactive
b. Mainframe computers are mostly batch systems with many users
c. Protection is much more important on mainframe computers
d. All of the others - ✔️✔️d
_____ are used to model devices that consist of a collection of randomly addressable
blocks such as disks
a. A character special file
b A separate special file
c. A block special file
d. A pipe special file - ✔️✔️c
OS manage the system security such as authentication, protecting the system from
unwanted intruders
a. Security
b. Authentication
c. Protection
d. Block access - ✔️✔️c
The UNIX command interpreter, or GUI
a. shell
b. prompt
c. command
d. compiler - ✔️✔️a
Which of these statements about virtual memory are true?
a. Gives the ability to run programs larger than the machine's physical memory by
moving pieces back and forth between RAM and disk
,b. Largely magnetic-tape based
c. Virtual Memory is a external memory
d. Enabled the ability to have a program dynamically link on a library at run time instead
of having it compiled in - ✔️✔️a d
Which of these statements about virtual memory are not true?
a. Gives the ability to run programs larger than the machine's physical memory by
moving pieces back and forth between RAM and disk
b. Enabled the ability to have a program dynamically link on a library at run time instead
of having it compiled in
c. None of others - ✔️✔️c
System calls
a. Permit application programs to access protected resources
b. The interface between user programs and the OS
c. The GUI between user program and the OS - ✔️✔️a b
____is a sort of pseudofile that can be used to connect to processes
a. A block
b. A pipe
c. A specific file
d. A block file - ✔️✔️b
Put the steps in making a system call in order
1. System calls may vary from one OS to another
2. System calls are like procedures: take parameters, calling routine waits for response
(a call to an OS service)
3. Once a system call occurs control passes to a specific routing in system mode. If the
parameters are correct and legal the request will be executed (a trap into the OS code)
a. 1, 2, 3
b. 2, 3, 1
c. 3, 1, 2
d. 3, 2, 1 - ✔️✔️b
What is not a main function of an operating system?
a. Provide the users with an extended (virtual) machine
b. Manage the I/O devices
c. Provide user interfaces
d. Support virtual memory - ✔️✔️c
MS-DOS is a example of ....
a. Monolithic system
b. Layered System
c. Virtual Machine
,d. Client-server model - ✔️✔️a
What is the main characteristic of embedded operating system?
a. Multiple CPU
b. Time-sharing
c. Many I/O devices
d. Restriction of memory size, speed of CPU, screen size, powers - ✔️✔️d
Which of the following statements is incorrect about user mode and kernel mode?
a. In kernel mode, the OS can execute every instruction in the instruction set
b. In user mode, user program can execute only a subset of instructions
c. Having two modes of operation helps prevent user programs from accessing critical
instructions
d. None of the others - ✔️✔️d
A time-sharing system is
a. Another name for a batch system
b. A multi-user, multi-process, interactive system
c. All of the others
d. None of the others - ✔️✔️b
Which of these statements about Microkernel are true?
a. The modules run user mode `\rightarrow` protection against bugs
b. All the layers went in the kernel
c. Resist crashing the entire system
d. All of the others - ✔️✔️a
An the OS concept, the software can be divided into 2 important modes
a. User mode
b. Supervisor mode
c. File mode
d. Management mode - ✔️✔️a b
Kernel mode is defined that _______
a. The mode has complete access to all the hardware
b. The mode can execute any instruction the machine is capable of executing
c. The mode is forbidden do I/O or control the machine
d. All of the others - ✔️✔️a b
The virtual machine
a. Can run any OS that will run directly on the bare hardware
b. Supports to run only OS at the same time
c. None of the others
d. Is identical to the true hardware - ✔️✔️a d
, Which of these statements about Layered System are not true?
a. Bottom layer is the user interface
b. Layers are selected so that each one uses functions, operations and services of only
lower-level layers
c. The highest layer is the user interface
d. The highest layer is hardware - ✔️✔️a d
_______ is the rapid switching of the CPU between multiple processes in memory
a. Multi-programming
b. Multi-paging
c. Multi-processes
d. Multi-scheduling - ✔️✔️a
Which of these statements about Microkernel are not true?
a. Resist crashing the entire system
b.Achieve high reliability by splitting the OS into small, well-defined modules
c. The modules run user mode to protection against bugs
d. None of the others - ✔️✔️d
If the system passes control to a user program, the ____ mode switches to the ____
mode
a. kernel/user
b. user/kernel
c. supervisor/user
d. hardware/software - ✔️✔️a c
Which of these statements about Batch service in Mainframe OS are true?
a. CPU is often idle, all jobs are kept on a disk
b. Process routine job without interactive user present
c. The OS always residents in memory and transfer control automatically from one job
to the next in the sequence requested jobs
d. None of the others - ✔️✔️a c
1. It is a list of memory locations (set of addresses) from 0 to some maximum, which the
process can read and write
2. It make the different programs think they have the hardware on their own
What's is it?
a. Address space
b. Process
c. Virtual Memory
d. System call - ✔️✔️a
1. The mechanism allows a child process to inherit a communication channel from its
parent; data written to one end of it can be read at the other hardware on their own
2. A mechanism for passing data among processes
What's is the mechanism?
_____ are used to model printers, modems, and other devices that accept or output a
character stream
a. A character special file
b. A separate special file
c. A block special file
d. A pipe special file - ✔️✔️a
Which of these statements about Monolithic Systems are true?
a. A set of service procedures that carry out the system calls
b. A set of utility procedures that Help the service procedures
c. A main program that invokes the requested service procedure
d. All of others - ✔️✔️a
Which is the difference between personal computers and mainframe computers?
a. Personal computers are always interactive
b. Mainframe computers are mostly batch systems with many users
c. Protection is much more important on mainframe computers
d. All of the others - ✔️✔️d
_____ are used to model devices that consist of a collection of randomly addressable
blocks such as disks
a. A character special file
b A separate special file
c. A block special file
d. A pipe special file - ✔️✔️c
OS manage the system security such as authentication, protecting the system from
unwanted intruders
a. Security
b. Authentication
c. Protection
d. Block access - ✔️✔️c
The UNIX command interpreter, or GUI
a. shell
b. prompt
c. command
d. compiler - ✔️✔️a
Which of these statements about virtual memory are true?
a. Gives the ability to run programs larger than the machine's physical memory by
moving pieces back and forth between RAM and disk
,b. Largely magnetic-tape based
c. Virtual Memory is a external memory
d. Enabled the ability to have a program dynamically link on a library at run time instead
of having it compiled in - ✔️✔️a d
Which of these statements about virtual memory are not true?
a. Gives the ability to run programs larger than the machine's physical memory by
moving pieces back and forth between RAM and disk
b. Enabled the ability to have a program dynamically link on a library at run time instead
of having it compiled in
c. None of others - ✔️✔️c
System calls
a. Permit application programs to access protected resources
b. The interface between user programs and the OS
c. The GUI between user program and the OS - ✔️✔️a b
____is a sort of pseudofile that can be used to connect to processes
a. A block
b. A pipe
c. A specific file
d. A block file - ✔️✔️b
Put the steps in making a system call in order
1. System calls may vary from one OS to another
2. System calls are like procedures: take parameters, calling routine waits for response
(a call to an OS service)
3. Once a system call occurs control passes to a specific routing in system mode. If the
parameters are correct and legal the request will be executed (a trap into the OS code)
a. 1, 2, 3
b. 2, 3, 1
c. 3, 1, 2
d. 3, 2, 1 - ✔️✔️b
What is not a main function of an operating system?
a. Provide the users with an extended (virtual) machine
b. Manage the I/O devices
c. Provide user interfaces
d. Support virtual memory - ✔️✔️c
MS-DOS is a example of ....
a. Monolithic system
b. Layered System
c. Virtual Machine
,d. Client-server model - ✔️✔️a
What is the main characteristic of embedded operating system?
a. Multiple CPU
b. Time-sharing
c. Many I/O devices
d. Restriction of memory size, speed of CPU, screen size, powers - ✔️✔️d
Which of the following statements is incorrect about user mode and kernel mode?
a. In kernel mode, the OS can execute every instruction in the instruction set
b. In user mode, user program can execute only a subset of instructions
c. Having two modes of operation helps prevent user programs from accessing critical
instructions
d. None of the others - ✔️✔️d
A time-sharing system is
a. Another name for a batch system
b. A multi-user, multi-process, interactive system
c. All of the others
d. None of the others - ✔️✔️b
Which of these statements about Microkernel are true?
a. The modules run user mode `\rightarrow` protection against bugs
b. All the layers went in the kernel
c. Resist crashing the entire system
d. All of the others - ✔️✔️a
An the OS concept, the software can be divided into 2 important modes
a. User mode
b. Supervisor mode
c. File mode
d. Management mode - ✔️✔️a b
Kernel mode is defined that _______
a. The mode has complete access to all the hardware
b. The mode can execute any instruction the machine is capable of executing
c. The mode is forbidden do I/O or control the machine
d. All of the others - ✔️✔️a b
The virtual machine
a. Can run any OS that will run directly on the bare hardware
b. Supports to run only OS at the same time
c. None of the others
d. Is identical to the true hardware - ✔️✔️a d
, Which of these statements about Layered System are not true?
a. Bottom layer is the user interface
b. Layers are selected so that each one uses functions, operations and services of only
lower-level layers
c. The highest layer is the user interface
d. The highest layer is hardware - ✔️✔️a d
_______ is the rapid switching of the CPU between multiple processes in memory
a. Multi-programming
b. Multi-paging
c. Multi-processes
d. Multi-scheduling - ✔️✔️a
Which of these statements about Microkernel are not true?
a. Resist crashing the entire system
b.Achieve high reliability by splitting the OS into small, well-defined modules
c. The modules run user mode to protection against bugs
d. None of the others - ✔️✔️d
If the system passes control to a user program, the ____ mode switches to the ____
mode
a. kernel/user
b. user/kernel
c. supervisor/user
d. hardware/software - ✔️✔️a c
Which of these statements about Batch service in Mainframe OS are true?
a. CPU is often idle, all jobs are kept on a disk
b. Process routine job without interactive user present
c. The OS always residents in memory and transfer control automatically from one job
to the next in the sequence requested jobs
d. None of the others - ✔️✔️a c
1. It is a list of memory locations (set of addresses) from 0 to some maximum, which the
process can read and write
2. It make the different programs think they have the hardware on their own
What's is it?
a. Address space
b. Process
c. Virtual Memory
d. System call - ✔️✔️a
1. The mechanism allows a child process to inherit a communication channel from its
parent; data written to one end of it can be read at the other hardware on their own
2. A mechanism for passing data among processes
What's is the mechanism?
