M.C.A - Operating System Short Questions. – G.VeeraRaghavaiah
1. Buffering:- In IPC one process send messages to the other process. Sending process is called “Sender”, receiving process is called “Receiver”. If the receiver is not yet to ready to receive the message that message is temporarily stored in “Buffer “ i.e., known as buffering. Such a messages that are waiting is buffer is known as the “Message Queue”.
2. Child Process:- In multi user ‘OS’ , if one process creates other process created process is called Child Process.
3. Parent process:- In multi user ‘OS’ . if one process creates other process creator is called “Parent Process”.
4. Component Name:- In Unix if want to refer any directory, we can search entire tree structure from “root” on words.
For Ex:- / bin /
user bin
bin
We have to specify full path names each part of the full path name will be treated as “Component” each component name is locked in the directory.
5. Device Independent:- in Unix & copy / dev / hyt file towrite
Here we take input from the terminal and with it inot the file file to write. Here the program does not need to know whether it is reading from ( or writing) to a file or device, i.e., called device independence.
6. Directory:- A directory is a collection of names each of which referencing to a file or another directory. If a name leads another directory then it is a collection of names.
7. Exec v:- int excev(char * programname, char * arg[]);
Here the program programname is run in the calling process. The program in the calling process is over written and will no longer exist. The arguments are in the argument vector argv which is an array of strings that is an array which is an array of pointers to characters.
8. Fork:- int fork(void); A new process is created that is an exact copy of the process making the system call.
9. FIFO:- We can use some idea about inter process communication through a technique is called named pipes(called fifo) when we read from pipe, we can get source bites.
10. File:- A file is a collection of data and information.
11. Open file:- Opening a file creat an operating system object called an open file. The open file is logically connected to the file you named in the open system call.
12. File Location:- An open file has a file location associated with it . it is the offset in the file where the next read or with will start.
13. Flat name space:- If the root directory could contain only file names and not dir4ctly names is called a flat name space.
14. Two level name space:- A two level name space is a hierarchy that is limited only two levels, so only the root directory contain other directories.
15. Hierarchical file naming system of name lookup:- In UNIX hierarchical structure each directory is a collection of names, and all the names in a directory are unique. A directory for forms a name space and a directory also include the mapping from each name or directory it refers to. So gives a name and directory, you can find the name (or) a directory the name refers to this called “name look up”.
16. Filter:- A program whose main function is to read a sequence of bits from its standard input and trans form the stream in some way, and then write to the standard output is called “Filter”.
17. Inter process communication:- Using process system calls we can send arguments to a new process to communicate with each other while they are running. We can this “IPC”.
18. Meta information:- Information about information.
19. Micro kernal:- New OS – in mid 1980’s at Carnegie – Mellon University. Functionally provided by the process running out side the kernel.
20. Open file:- In order to use a file you first need to ask for it by name. This is called opening the file opening, a file creates an OS object “Open File”.
21. Open file Identifier:- The named file is opened, and an identifier, the open file identifier is return. This a file location is initialized to ‘O’. the flags argument is one of:-
O : Open for reading
1 : Open for writing
2 : Open for reading & writing
22. Program:- A program is a static object that can exist in a file it contains the instruction.
23. Process:- A process is a dynamic object that is a program in execution. A process is a sequence of instructions to execute.
24. Process Hierarchical:- If one process creates another process, creator of the process is called parent process. The parent child relationship can be shown in hierarchical representation is known as process hierarchical.
25. System call interface:- It is the description of the set of system calls that are implemented by the operating system.
26. Shell:- A shell is a command language interpreter it decides which will be executed by the processor next from the waiting queue.
27. Standard Input
28. Standard Output:- Open files are named with integers are called open file identifier. In Unix open file identifier is set to ‘o’ is called standard input. Open file identifier is set to 1 is called standard output.
29. Redirection:- When shell starts the program standard input and standard output are normally from the user terminal, but they can be changed by a method is called redirection.
30. Macintosh “OS” :- It brings significant challenge to the domination if the IBM PC computer market for Apple Macintosh Computer. It provides full fledged graphical interface and significantly easier to use.
31. Connection Protocol:- Communicating with server by establishing a connection with the server . Ex:- telephone system.
32. Connectionless Protocol:- In connectionless protocol there is no interaction with the server. Ex:- postal system.
33. Message Passing:- Messages are connectionless protocol. Each messages standards on its own and is not connected with other messages.
34. Pipe:- A pipe is a connection protocol for communication between processes.
35. Decomposition Pattern:- for decomposing a system, we can decompose into
· A Strict hierarchy of procedures
· A DAG of procedures.
· A Sequence of levels where each level is a module.
· A collection of methods that export and import interfaces from other modules.
36. Directed Acyclic Graph(DAG):- If we consider any tree structure none of the nod having two parents. If no procedure could be called by two other procedures to the designers of these generalized the structure a little to also a node to have to parents, but still no cyclic were allowed this is called a Directed Acyclic Graph (or) DAG.
37. Design Problem:- During the program design you, repeatedly come across situations where you need to achieve a certain goal in a certain situation subject to certain constraints . this is what we call a design problem.
38. Design Skill:- This consists of being able to move around into design space and find good points. This includes skills in a evaluating designs.
39. Design Space:- One way to look at design is as a search thorough the design space of the problem.
40. Embedded system:- These are all micro chip based systems. Many of these are data reliant and could therefore be the source of problems and different levels. A resolution plan is offered. The current languages are embeddable. This means that they are implemented as procedure library that can be included in any program.
41. Implementation:- In level struct5ure each level has an interface which is used by the next level up. Each interface is supported by the implementation below the interface.
42. Interface:- An interface is a specification of the capabilities of a level. An interface is a contract between the implement of the interface and the clients of the interface.
43. Interface Design :- Range of possibilities in the design of an interface is called interface design.
44. Language interface:- In language interface where the upper level might be a user or a program that sends a lower level a program to execute.
45. Little Languages:- In software design technique two level structure are used called little languages. The idea of little languages is that it provide interactive access to a collection of functions related to a task.
46. scripting Languages:- Little languages can bring some power of programmability to the user level. Scripting languages like shell programming languages. Little language idea is so useful that there re many examples in commercial and non commercial products.
47. Modularity:- is key principle. In software design is modularity.
48. let of modules to get the advantage of modularity. Two level implementation : modularity plays major roles in ‘OS’ design. Here two level implementation plays major role. Here there are just two levels. Upper level is running on lower level module.
49. Policy & Mechanism:- In two level implementation often the lower level implements the policy.
Upper level : Program
Lower level : Language
49.Connection Protocol:- Static Telephone system.
50. Connectionless Protocol:- Dynamic postal system.
No comments:
Post a Comment