Operating System MCQs with Answers
Practice important Operating System MCQs with answers and explanations.
Chapter: 44
Q1221:
Which method of space allocation uses a linked list of disk blocks?
A. Contiguous allocation
B. Linked allocation
C. Indexed allocation
D. Direct allocation
Correct Answer:
B
Chapter: 44
Q1222:
What is a UNIX file descriptor?
A. A pointer to the file's inode
B. A pointer to the file's data block
C. A pointer to the file's permissions
D. A pointer to the system-wide open file table
Correct Answer:
A
Chapter: 44
Q1223:
Which command is used to display the default mask value in UNIX?
A. umask
B. ls
C. chmod
D. umask -v
Correct Answer:
A
Chapter: 44
Q1224:
What does the 'r' permission in UNIX allow you to do?
A. Execute the file
B. Read the file
C. Write to the file
D. Delete the file
Correct Answer:
A
Chapter: 44
Q1225:
What is the main disadvantage of the contiguous allocation method?
A. External fragmentation
B. File size estimation difficulty
C. Slow access to files
D. Supports limited types of access
Correct Answer:
B
Chapter: 44
Q1226:
Fill in the blank: The chmod command in UNIX is used to _________.
A. set file permissions
B. delete files
C. create directories
D. list files
Correct Answer:
A
Chapter: 45
Q1227:
What does indexed allocation support in file systems?
A. Sequential access
B. Direct access without external fragmentation
C. Random access
D. Indirect access
Correct Answer:
B
Chapter: 45
Q1228:
In UNIX systems, which attribute determines the maximum file size?
A. Disk block size
B. Number of direct pointers
C. File system size
D. Number of indirect pointers
Correct Answer:
B
Chapter: 45
Q1229:
A UNIX inode contains which of the following?
A. File data
B. Direct and indirect pointers to file blocks
C. File metadata
D. Block size
Correct Answer:
B
Chapter: 45
Q1230:
The FAT file system uses which of the following for space allocation?
A. Linked list of files
B. File Allocation Table (FAT)
C. Multi-level index
D. Linked directory entries
Correct Answer:
B
Chapter: 45
Q1231:
What is a key feature of a bit vector in free-space management?
A. It links free blocks in a list
B. It maps each block to a 1 or 0 based on its availability
C. It keeps track of file metadata
D. It allocates new files directly
Correct Answer:
B
Chapter: 45
Q1232:
Free space in a file system can be managed using a _________.
A. File Allocation Table (FAT)
B. Bit vector
C. Multi-level index
D. Disk schedule
Correct Answer:
B
Chapter: 45
Q1233:
Which free-space management technique uses a linked list to manage free blocks?
A. Bit vector
B. Linked list
C. Grouping
D. Counting
Correct Answer:
B
Chapter: 45
Q1234:
A block in the UNIX system’s file manager can hold up to ________ direct pointers.
A. 10
B. 15
C. 20
D. 25
Correct Answer:
A
Chapter: 45
Q1235:
A double indirect block pointer in UNIX file systems refers to which of the following?
A. Points to data blocks directly
B. Points to a block containing addresses of blocks that contain data
C. Points to file metadata
D. Points to an indirect block pointer
Correct Answer:
B
Chapter: 45
Q1236:
Which disk scheduling algorithm is most efficient in terms of minimizing seek time?
A. FCFS
B. SSTF
C. C-SCAN
D. C-Look
Correct Answer:
B
Chapter: 45
Q1237:
In the UNIX file system, the maximum file size depends on the size of ________.
A. Inode block size
B. Disk addresses
C. File Allocation Table
D. Directory entry
Correct Answer:
B
Chapter: 45
Q1238:
The best-case I/O operations for inserting a block after the 50th block will be ________.
A. 100+1+2
B. 50+1+2
C. 50+1+100
D. 103+2
Correct Answer:
A
Chapter: 45
Q1239:
The process of linking free blocks together in memory for disk management is known as ________.
A. Free list linking
B. Counting
C. Grouping
D. Bit vectoring
Correct Answer:
A
Chapter: 45
Q1240:
The approach of maintaining free blocks by storing the addresses of n free blocks in the first free block is called ________.
A. Bit vector
B. Linked list
C. Grouping
D. Counting
Correct Answer:
C