Computer Operating System Questions and Answers

Answer: B

Correct answer: CONFIG.SYS, AUTOEXEC.BAT

DOS reads CONFIG.SYS first, loading the device drivers and setting FILES, BUFFERS and the rest, then loads COMMAND.COM, which runs AUTOEXEC.BAT. The order matters: drivers must be in place before the commands that use them are executed.

Answer: C

Correct answer: operating environment

An operating environment is a layer placed over the operating system to make it easier to use - a menu shell or a graphical environment such as early Windows over MS-DOS - presenting the same facilities in a friendlier form. Timesharing and multitasking are things the operating system does, not aids to using it.

Answer: D

Correct answer: the language which communicates with the computer using only binary digits

Machine language is the processor’s own code: instructions written as patterns of 0s and 1s that the hardware executes directly, with no translation. It is the only language a computer truly understands; everything else must be translated into it first.

Answer: C

Correct answer: must be "loaded" before execution

Object code is the machine code a translator produces, but it is not yet runnable: external references must be resolved by the linker and the addresses relocated to wherever the program is placed, which the loader does before control is passed to it.

Answer: A

Correct answer: Assembly and output

Turning symbolic labels into actual addresses and emitting the machine instructions is the last phase of compilation - assembly and output. Code generation has already chosen the instructions; this phase fixes their addresses and writes the object module.

Answer: B

Correct answer: 1

A semaphore guarding a critical section starts at 1: the first process to call wait() takes the count to 0 and enters, and every other process blocks until that one calls signal(). Only one process is inside at a time, which is exactly mutual exclusion.

Answer: A

Correct answer: config.sys

A driver ending in .SYS is loaded by a DEVICE= line in CONFIG.SYS, which DOS reads early in the boot before the command interpreter starts. The .COM form of the same driver would instead be run from AUTOEXEC.BAT.

Answer: A

Correct answer: COPY

COPY takes a named file (or a group matched by wildcards) and writes it to another disk or directory. DISKCOPY duplicates a whole diskette track by track, RENAME only changes a name, and FORMAT erases the disk and prepares it for use.

Answer: A

Correct answer: Config.sys

BUFFERS is a device and memory setting read by DOS as it loads, so it belongs in CONFIG.SYS. AUTOEXEC.BAT runs afterwards, once the system is already configured.

Answer: C

Correct answer: contains the address of the memory location that is to be read from or stored into

The memory address register holds the address of the location the processor is about to read or write, and drives it onto the address bus; the memory data register holds the value that travels back or forth on the data bus. One names the place, the other carries the contents.