Description : Which of the following information about the UNIX file system is not correct? (A) Super block contains the number of i-nodes, the number of disk blocks, and the start of the list of free disk blocks. (B ... Each i-node is 256-bytes long. (D) All the files and directories are stored in data blocks.
Last Answer : (C) Each i-node is 256-bytes long.
Description : Write syntax for following commands: i)Sleep ii)Kill
Last Answer : i)sleep Syntax: sleep NUMBER[SUFFIX]… sleep OPTION ii) kill Syntax: kill pid
Description : Enlist different file allocation methods? Explain contiguous allocation method in detail.
Last Answer : From the user's point of view, a file is an abstract data type. It can be created, opened, written, read, closed and deleted without any real concern for its implementation. The implementation of a ... a times is difficult to estimate. 4. Compaction may be required and it can be very expensive.
Description : Describe any four file attributes
Last Answer : File attributes: Name: The symbolic file name is the only information kept in human readable form. Identifier: File system gives a unique tag or number that identifies file within file ... Last modification and last use. These data can be useful for protection, security and usage monitoring.
Description : List any four features of open source operating system.
Last Answer : 1. Open Source: open source OS code is freely available and it is community based development project. Multiple team's works in collaboration to enhance the capability of operating system and it is ... issuing a command in Linux Terminal or Shell. Linux can also run Windows applications if needed.
Description : List free space management techniques? Describe any one in detail.
Last Answer : A file system is responsible to allocate the free blocks to the file therefore it has to keep track of all the free blocks present in the disk. There are mainly four approaches by using which, the free ... block. This block contains a pointer to the next free disk block, and so on.
Description : List components of OS. Explain process management in detail.
Last Answer : List of System Components: 1. Process management 2. Main memory management 3. File management 4. I/O system management 5. Secondary storage management Process Management: The operating ... synchronization. 4. A mechanism for process communication. 5. A mechanism for deadlock handling.
Description : Define real time operating system. List its any four applications of it.
Last Answer : Real time Operating System: A real time system has well defined fixed time constraints. Processing should be done within the defined constraints -Hard and Soft real time system. OR The ... Applications: 1. Flight Control System 2. Simulations 3. Industrial control 4. Military applications
Description : Which switch should be used in the DIR command to view files in all directories ? 1) /P 2) /W 3) /S 4) /L
Last Answer : 3) /S
Description : Which switch should be used in the DIR command to view files in all directories ? 1 /P 2 /W 3 /S 4 /L
Last Answer : 3 /S
Description : Which of the following statement is not correct with reference to cron daemon in UNIX O.S? (A) The cron daemon is the standard tool for running commands on a predetermined schedule. (B) It starts ... command lines and the times at which they invoked. (D) Crontab for individual users are not stored.
Last Answer : (D) Crontab for individual users are not stored.
Description : In Unix, files can be protected by assigning each one a 9-bit mode called rights bits. Now, consider the following two statements: I. A mode of 641 (octal) means that the owner can read and write the file, other ... (B) Only II is correct (C) Both I and II are correct (D) Both I and II are incorrect
Last Answer : (C) Both I and II are correct
Description : Explain LRU page replacement algorithm for following reference string. 7 0 1 2 0 3 0 4 2 3 0 3 2 1 2 0 1 7 0 1 Calculate the page fault.
Last Answer : LRU: The Least Recently Used (LRU) page replacement policy replaces the page that has not been used for the longest period of time. LRU replacement associates with each page the time of that page's last use. ... in question so assume frame size as 3 or 4) LRU: Assume frame size=3
Description : Explain multithreading model in detail.
Last Answer : Many systems provide support for both user and kernel threads, resulting in different multithreading models. Following are three multithreading model: Many-to-One Model The many-to- ... True concurrency cannot be achieved. Multiple threads of kernel is an overhead for operating system
Description : Enlist the operating system tools. Explain any two in detail.
Last Answer : Following are the operating tools: User Management Security policy Device Management Performance Monitor Task Scheduler A) User management: User management includes everything ... routing tables, interface statistics, masquerade connections, and multicast memberships. # netstat -tulpn
Description : Explain PCB with diagram.
Last Answer : Each process is represented as a process control block (PCB) in the operating system. It contains information associated with specific process. Process State: It indicates current state of a process. ... . Each PCB gives information about a particular process for which it is designed.
Description : Explain Round Robin algorithm with suitable example.
Last Answer : It is preemptive scheduling algorithm. A small unit of time known as a time quantum or time slice is used for pre-emption of a currently running process. Ready queue is implemented as a circular ... has received 1 time quantum, the CPU returns to process P1 for an additional time quantum.
Description : State and describe types of scheduler.
Last Answer : There are three types of scheduler: Long term scheduler Short term scheduler Medium term scheduler 1. Long term scheduler: It selects programs from job pool and loads them into the ... scheduler works in close communication with long term scheduler for loading process into the main memory.
Description : What is purpose of system call? State two system calls with their functions.
Last Answer : System call provides an interface between a running program and operating system. It allows user to access services provided by operating system. This system calls are procedures written using C, ... send, receive messages transfer status information attach or detach remote devices.
Description : Describe sequential and direct access method.
Last Answer : Sequential access: Information from the file is processed in order i.e. one record after another. It is commonly used access mode. For example, editors and compilers access files in sequence. A read ... prevent the user from accessing portions of the file system that may not be part of his file.
Description : Explain partitioning and its types.
Last Answer : An important operation of memory management is to bring programs into main memory for execution by the processor. Partitioning is a technique that divides a memory into multiple partitions. These partitions ... in memory. For example: Consider following table with process and memory space.
Description : Explain deadlock? What are necessary conditions for deadlock?
Last Answer : In multiprogramming environment, several processes may compete for a finite number of resources. A process requests resources and if the resources are not available then the process enters into the ... Each process is waiting for the resources held by other waiting processes in circular form.
Description : Describe I/O Burst and CPU Burst cycle with neat diagram.
Last Answer : CPU burst cycle: It is a time period when process is busy with CPU. I/O burst cycle: It is a time period when process is busy in working with I/O resources. A process execution consists ... cycle and so on. The final CPU burst cycle ends with a system request to terminate execution.
Description : With neat diagram explain inter process communication model.
Last Answer : Inter-process communication: Cooperating processes require an Interprocess communication (IPC) mechanism that will allow them to exchange data and information. There are two models of IPC 1. ... a communication link between them. Between each pair of processes exactly one communication link.
Description : Enlist types of operating system. Explain multiprogramming OS in detail.
Last Answer : Types of operating system 1.Batch Systems 2.Multiprogramming 3.Multitasking 4.Time-Sharing Systems 5.Desktop Systems 6.Distributed system 7.Clustered system 8.Real Time system: Multiprogramming ... multiprogramming: user can open word, excel, access and other applications in a system.
Description : Define virtual memory
Last Answer : Virtual memory is a memory management capability of an operating system (OS) that uses hardware and software to allow a computer to compensate for physical memory shortages by temporarily transferring data ... can be placed in overlays, but can concentrate instead on the problem to be programmed.
Description : Explain any four scheduling criteria.
Last Answer : 1. CPU utilization: In multiprogramming the main objective is to keep CPU as busy as possible. CPU utilization can range from 0 to 100 percent. 2.Throughput: It is the number of processes ... fairly early and can continue computing new results while previous results are being output to the user.
Description : Draw process state diagram.
Last Answer : process state diagram
Description : Explain any 4 services provided by OS.
Last Answer : 1.User Interface: All operating systems have a user interface that allows users to communicate with the system. Three types of user interfaces are available: a. Command line interface ( ... to system resources. Security is provided by user authentication such as password for accessing information.
Description : Linux command to create nested directories (a directory inside a directory) -Web-Development
Last Answer : answer:
Description : In Unix operating system, special files are used to : (A) buffer data received in its input from where a process reads (B) provide a mechanism to map physical device to file names (C ... pointers associated with i-nodes (D) store information entered by a user application program or utility program
Last Answer : (B) provide a mechanism to map physical device to file names
Description : The Unix command: $ vi file1 file2 (A) Edits file1 and stores the contents of file1 in file2 (B) Both files i.e. file1 and file2 can be edited using ex' command to travel between files (C) Both ... using the mv' command to move between the files (D) Edits file1 first, saves it and the edits file2
Last Answer : (B) Both files i.e. file1 and file2 can be edited using ‘ex’ command to travel between files
Description : Unix command to change the case of first three lines of file “shortlist” from lower to upper (1) $ tr ‘[a-z]’ ‘[A-Z]’ shortlist | head-3 (2) $ head-3 shortlist | tr ‘[a-z]’ ‘[A-Z]’ (3) $ tr head-3 shortlist ‘[A-Z]’ ‘[a-z]’ (4) $ tr shortlist head-3 ‘[a-z]’ ‘[A-Z]’
Last Answer : (2) $ head-3 shortlist | tr ‘[a-z]’ ‘[A-Z]’
Description : Is there a unix command to reverse the lines in a file?
Last Answer : answer:tac tac (cat spelled backwards) works like cat, but reverse the order of the lines (last line is written out first).
Description : Consider the following UNIX command: sort temp; head -30
Last Answer : (C) Sort, taking the input from "in" and writing the output to "temp" then prints 30 lines from temp on terminal. Finally "temp" is removed.
Description : What will be the output of the following Unix command ? $rm chap0\[1 - 3\] (A) Remove file chap0[1 - 3] (B) Remove file chap01, chap02, chap03 (C) Remove file chap\[1 - 3\] (D) None of the above
Last Answer : (A) Remove file chap0[1 - 3]
Description : In Unix, the command to enable execution permission for file “mylife” by all is ................ (A) Chmod ugo+X myfile (B) Chmod a+X myfile (C) Chmod +X myfile (D) All of the above
Last Answer : (D) All of the above
Description : What is the function of following UNIX command? WC - lb& (A) 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. (B) It runs ... (D) It copies the l ' numbers of lines of program from file, a, and stores in file b.
Last Answer : (B) 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.
Description : Why when I somtimes download an application online it sometimes stores application and all files in download file and not in application folder?
Last Answer : is it ok to just move applcstion folder tmfrom download folder to application folder and leave all the other text documents and other folders in download folder?
Description : It can contain files as well as folders. (a) Windows (b) Folder (c) Dialog (d) File -Technology
Last Answer : (b) Folder is a location in which you can store files/folders and sub-folders.
Description : Which of the following statements is false concerning file names? a) Files may share the same name or the same extension but not both b) Every file in the same folder must have a unique name c) File extension is another name for file type d) None of these
Last Answer : d) None of these
Description : Does archiving files and directories into ZIP or RAR enhance defragmentation?
Last Answer : No because writing and deleting files is what causes fragmentation. Especially writing such large files to an already fragmented disk. Just get Diskeeper and let it run in the background. It's a very ... have to do any tricks, or remember everything. My disks are never fragmented when I check them.
Description : Data (information) is stored in computer as ________: a) Directories b) Files c) Floppies d) Matter e) None of The Above
Last Answer : b) Files
Description : Data (information) is stored in computers as- 1) Files 2) Directories 3) Floppies 4) Matter
Last Answer : 1) Files
Description : Digital Forensics entails _____. A. Accessing the system's directories viewing mode and navigating through the various systems files and folders B. Undeleting and recovering lost ... identification, preservation, recovery, restoration and presentation of digital evidence from systems and devices
Last Answer : D. The identification, preservation, recovery, restoration and presentation of digital evidence from systems and devices
Description : Which of the following operations can be performed by using FTP. i) Connect to a remote host ii) Select directory iii) Define the transfer mode iv) List file available A) i, and ii only B) i, ii and iii only C) ii, iii and iv only D) All i, ii, iii and iv
Last Answer : D) All i, ii, iii and iv
Last Answer : C) ii, iii and iv only
Description : ____ is a small picture on screen that depicts program, file or folder: a) Start Bottom b) Task Bar c) Icon d) Pixel e) Cursor
Last Answer : c) Icon
Description : Which of the codes given below contains only the correct statements? Statements: (i) Venn diagram is a clear method of notation (ii) Venn diagram is the most direct method of testing the validity of categorical syllogisms (iii) ... ) (C) (ii) (iii) & (iv) (D) (i) (iii) & (iv)
Last Answer : Answer: B
Description : Write the name of layers that perform the following functions in OSI : I. Data Encryption II. Error Correction III. File Transfer IV. Data Encoding
Last Answer : 1. Data Encryption-Presentation Layer 2. Error Correction-Data link layer and Transport layer 3. File Transfer-Application layer 4. Data Encoding-Presentation layer