Computer Operating System Questions and Answers

Answer: C

Correct answer: DIR/B

The /B (bare) switch lists names alone, with no heading, no size, date or time, and no summary line - which is what makes it useful for piping into another command or capturing to a file. /W gives a wide listing and /S descends into subdirectories.

Answer: B

Correct answer: lexical analysis

Lexical analysis is the first phase: it scans the source character by character and groups the characters into tokens - identifiers, keywords, constants, operators - classifying each. Syntax analysis then takes that stream of tokens and checks it against the grammar of the language.

Answer: C

Correct answer: SORT/R < filename

The /R switch makes SORT order the lines in reverse, and the file is fed in with < because SORT is a filter that reads standard input.

Answer: A

Correct answer: a part of data to be displayed

Scissoring, or clipping, discards the parts of a picture that fall outside the window, so only the portion inside is drawn. It is what lets a small viewport show a region of a much larger drawing without the rest spilling across the screen.

Answer: D

Correct answer: None of the above

Pseudocode is not a programming language at all: it is a notation for writing an algorithm in a mixture of structured English and code-like constructs, so the logic can be set out and reviewed. No compiler accepts it, and it must be rewritten in a real language before it can run.

Answer: B

Correct answer: Operating system

Without an operating system nothing can manage the processor, memory, files and devices, so no other program - including a compiler or an interpreter - can be loaded or run. Translators are needed only if you intend to write programs.

Answer: C

Correct answer: TIME

TIME displays the current time and offers to change it; typed with a value it sets the clock directly. DATE does the same for the date.

Answer: D

Correct answer: BAK

The extension .BAK marks a backup copy, written automatically by many programs before they overwrite the original, so the previous version can be recovered. TXT holds text, COM an executable, and BAS a BASIC source file.

Answer: C

Correct answer: cross compiler

A cross compiler runs on one machine but generates code for another, which is how software is built for a target too small to host a compiler - an embedded processor or a new machine that does not yet run anything. Optimising, one-pass and multipass describe how a compiler works, not what it targets.

Answer: C

Correct answer: creation of more optimal matrix.

Improving the intermediate representation - removing common subexpressions, hoisting loop-invariant code, folding constants - is done before any target machine is considered, so it belongs to machine-independent optimisation. Register allocation and instruction selection depend on the machine and come later.