UNIX Question and Answer – File System Structure
UNIX MCQ – Multiple Choice Questions for exam, interview, and Entrance Test
1. What is the root directory in UNIX?
a) /
b) /
c) /root
d) /home
Answer: a) /
Explanation: The root directory in UNIX is denoted by a single forward slash (/) and serves as the starting point of the file system hierarchy.
2. Which command is used to list the contents of a directory in UNIX?
a) list
b) ls
c) dir
d) show
Answer: b) ls
Explanation: The ls command is used to list the contents of a directory in UNIX.
3. What is the file type of a symbolic link in UNIX?
a) Regular file
b) Directory
c) Symbolic link
d) Special file
Answer: c) Symbolic link
Explanation: Symbolic links in UNIX represent references to other files or directories.
4. Which character is used to denote a hidden file or directory in UNIX?
a) !
b) .
c) *
d) #
Answer: b) .
Explanation: In UNIX, files or directories prefixed with a dot (.) are considered hidden.
5. What is the purpose of the mkdir command in UNIX?
a) Remove a directory
b) Rename a directory
c) Create a new directory
d) List directory contents
Answer: c) Create a new directory
Explanation: The mkdir command is used to create a new directory in UNIX.
6. Which command is used to display the current working directory in UNIX?
a) dir
b) pwd
c) path
d) currdir
Answer: b) pwd
Explanation: The pwd command is used to display the current working directory in UNIX.
7. What is the file type of a regular file in UNIX?
a) Regular file
b) Directory
c) Symbolic link
d) Special file
Answer: a) Regular file
Explanation: Regular files in UNIX contain data and are denoted by the absence of any special designation.
8. Which command is used to create a symbolic link in UNIX?
a) ln -s
b) link -s
c) sym
d) lnk
Answer: a) ln -s
Explanation: The ln command with the -s option is used to create symbolic links in UNIX.
9. What is the purpose of the rmdir command in UNIX?
a) Create a directory
b) Remove a directory
c) Rename a directory
d) List directory contents
Answer: b) Remove a directory
Explanation: The rmdir command is used to remove empty directories in UNIX.
10. Which command is used to display detailed information about files and directories in UNIX?
a) info
b) details
c) stat
d) fileinfo
Answer: c) stat
Explanation: The stat command displays detailed information about files and directories in UNIX.
11. What is the purpose of the touch command in UNIX?
a) Create a new file
b) Change file permissions
c) Change file timestamps
d) Remove a file
Answer: c) Change file timestamps
Explanation: The touch command is used to change the access and modification timestamps of a file in UNIX.
12. Which command is used to remove files or directories in UNIX?
a) rm
b) del
c) erase
d) remove
Answer: a) rm
Explanation: The rm command is used to remove files or directories in UNIX.
13. What is the purpose of the ln command in UNIX?
a) Create a new file
b) Create hard links
c) Change file permissions
d) List directory contents
Answer: b) Create hard links
Explanation: The ln command is used to create hard links to files in UNIX.
14. Which command is used to change the permissions of a file or directory in UNIX?
a) mod
b) perm
c) chmod
d) chperm
Answer: c) chmod
Explanation: The chmod command is used to change the permissions of a file or directory in UNIX.
15. What is the purpose of the find command in UNIX?
a) Search for files and directories
b) Display directory contents
c) Create new files
d) List running processes
Answer: a) Search for files and directories
Explanation: The find command is used to search for files and directories based on various criteria in UNIX.
16. Which command is used to display the contents of a file in UNIX?
a) display
b) cat
c) print
d) read
Answer: b) cat
Explanation: The cat command is used to display the contents of a file in UNIX.
17. What is the purpose of the cp command in UNIX?
a) Move files or directories
b) Copy files or directories
c) Change file permissions
d) Rename files or directories
Answer: b) Copy files or directories
Explanation: The cp command is used to copy files or directories in UNIX.
18. Which command is used to display the file type of a file in UNIX?
a) type
b) file
c) ftype
d) filetype
Answer: b) file
Explanation: The file command is used to display the file type of a file in UNIX.
19. What is the purpose of the chmod command in UNIX?
a) Change file ownership
b) Change file permissions
c) Create a new file
d) Display file contents
Answer: b) Change file permissions
Explanation: The chmod command is used to change the permissions of a file or directory in UNIX.
20. Which command is used to display the size of files and directories in UNIX?
a) size
b) ls -s
c) du
d) filesize
Answer: c) du
Explanation: The du command is used to display the size of files and directories in UNIX.
21. What is the purpose of the mv command in UNIX?
a) Copy files or directories
b) Move files or directories
c) Create a new directory
d) Rename files or directories
Answer: b) Move files or directories
Explanation: The mv command is used to move files or directories in UNIX.
22. Which command is used to display the file system disk usage in UNIX?
a) df
b) du
c) fs
d) diskusage
Answer: a) df
Explanation: The df command is used to display the file system disk usage in UNIX.
23. What is the purpose of the ln command with the -s option in UNIX?
a) Create a hard link
b) Create a symbolic link
c) Rename a file
d) Copy a file
Answer: b) Create a symbolic link
Explanation: The ln command with the -s option is used to create symbolic links in UNIX.
24. Which command is used to create a new empty file in UNIX?
a) touch
b) newfile
c) create
d) mkfile
Answer: a) touch
Explanation: The touch command is used to create a new empty file in UNIX.
25. What is the purpose of the tar command in UNIX?
a) Compress files
b) Extract files from an archive
c) Create archives
d) List files in an archive
Answer: c) Create archives
Explanation: The tar command is used to create archives in UNIX, often used for backup purposes.
26. What is the purpose of the ls -l command in UNIX?
a) List directory contents in long format
b) List hidden files only
c) List directory contents with file sizes
d) List directory contents in alphabetical order
Answer: a) List directory contents in long format
Explanation: The ls -l command is used to display detailed information about files and directories in UNIX, including permissions, ownership, size, and modification time.
27. Which command is used to change the group ownership of a file or directory in UNIX?
a) chown
b) chgrp
c) chmod
d) chgrpown
Answer: b) chgrp
Explanation: The chgrp command is used to change the group ownership of a file or directory in UNIX.
28. What is the purpose of the pwd command in UNIX?
a) Print working directory
b) Print word count of a file
c) Print file permissions
d) Print file details
Answer: a) Print working directory
Explanation: The pwd command is used to print the current working directory in UNIX.
29. Which command is used to display the contents of a file in pages in UNIX?
a) more
b) cat
c) less
d) view
Answer: c) less
Explanation: The less command is used to display the contents of a file in pages in UNIX, allowing navigation through large files.
30. What is the purpose of the file command in UNIX?
a) Display file contents
b) Change file permissions
c) Determine file type
d) Compress files
Answer: c) Determine file type
Explanation: The file command is used to determine the type of a file in UNIX, such as whether it is a text file, binary file, or symbolic link.
31. Which command is used to remove a symbolic link in UNIX?
a) unlink
b) delink
c) rmlink
d) remove
Answer: a) unlink
Explanation: The unlink command is used to remove a symbolic link in UNIX.
32. What is the purpose of the umask command in UNIX?
a) Change file permissions
b) Display file permissions
c) Set default file permissions
d) Remove file permissions
Answer: c) Set default file permissions
Explanation: The umask command is used to set default file permissions in UNIX for newly created files and directories.
33. Which command is used to display the size of a file in UNIX?
a) size
b) filesize
c) ls -s
d) stat
Answer: c) ls -s
Explanation: The ls -s command is used to display the size of a file in UNIX, showing the number of blocks used by the file.
34. What is the purpose of the chmod +x command in UNIX?
a) Change file permissions to executable
b) Change file permissions to read-only
c) Change file permissions to writable
d) Change file permissions to hidden
Answer: a) Change file permissions to executable
Explanation: The chmod +x command is used to add execute permissions to a file in UNIX.
35. Which command is used to create a hard link in UNIX?
a) ln -h
b) link
c) hardlink
d) ln
Answer: d) ln
Explanation: The ln command is used to create hard links in UNIX.
36. What is the purpose of the find command with the -type d option in UNIX?
a) Search for directories only
b) Search for regular files only
c) Search for symbolic links only
d) Search for hidden files only
Answer: a) Search for directories only
Explanation: The find command with the -type d option is used to search for directories only in UNIX.
37. Which command is used to display the contents of multiple files in UNIX?
a) cat
b) more
c) head
d) tail
Answer: a) cat
Explanation: The cat command is used to concatenate and display the contents of multiple files in UNIX.
38. What is the purpose of the du command in UNIX?
a) Display disk usage of files and directories
b) Display file permissions
c) Display detailed file information
d) Display directory contents
Answer: a) Display disk usage of files and directories
Explanation: The du command is used to display disk usage of files and directories in UNIX.
39. Which command is used to create a new directory and its parent directories in UNIX?
a) mkdir -p
b) mkdir -m
c) mkdir -r
d) mkdir -d
Answer: a) mkdir -p
Explanation: The mkdir -p command is used to create a new directory and its parent directories in UNIX, creating intermediate directories as needed.
40. What is the purpose of the touch command with no arguments in UNIX?
a) Change file permissions
b) Display file details
c) Create a new empty file
d) Change file timestamps to the current time
Answer: c) Create a new empty file
Explanation: The touch command with no arguments is used to create a new empty file in UNIX.
41. Which command is used to remove a directory and its contents in UNIX?
a) rmdir
b) rmd
c) rm -r
d) remove
Answer: c) rm -r
Explanation: The rm -r command is used to remove a directory and its contents recursively in UNIX.
42. What is the purpose of the ln command with the -f option in UNIX?
a) Force creation of links
b) Create symbolic links
c) Create hard links
d) Remove links
Answer: a) Force creation of links
Explanation: The ln command with the -f option is used to force creation of links in UNIX, overwriting existing ones if necessary.
43. Which command is used to display the file system type of a file system in UNIX?
a) fstype
b) fs
c) df
d) stat
Answer: c) df
Explanation: The df command is used to display information about file systems in UNIX, including their type.
44. What is the purpose of the mount command in UNIX?
a) Unmount a file system
b) Display file system information
c) Mount a file system
d) Change file system permissions
Answer: c) Mount a file system
Explanation: The mount command is used to attach a file system to the system’s directory tree in UNIX.
45. Which command is used to display the inode number of a file in UNIX?
a) inum
b) inode
c) stat
d) ls -i
Answer: d) ls -i
Explanation: The ls -i command is used to display the inode number of a file in UNIX.
46. What is the purpose of the chown command in UNIX?
a) Change file permissions
b) Change file ownership
c) Change file type
d) Change file group
Answer: b) Change file ownership
Explanation: The chown command is used to change the ownership of a file or directory in UNIX.
47. Which command is used to display the number of lines, words, and characters in a file in UNIX?
a) lines
b) wc
c) count
d) stats
Answer: b) wc
Explanation: The wc command is used to display the number of lines, words, and characters in a file in UNIX.
48. What is the purpose of the ln command with the -d option in UNIX?
a) Create hard links
b) Create symbolic links
c) Delete links
d) Display file details
Answer: b) Create symbolic links
Explanation: The ln command with the -d option is used to create symbolic links in UNIX.
49. Which command is used to copy directories in UNIX?
a) cp
b) copy
c) cpdir
d) cp -r
Answer: d) cp -r
Explanation: The cp -r command is used to recursively copy directories in UNIX.
50. What is the purpose of the mv command with the -i option in UNIX?
a) Move files interactively
b) Move files forcefully
c) Move files silently
d) Move files recursively
Answer: a) Move files interactively
Explanation: The mv command with the -i option prompts the user before overwriting existing files during a move operation in UNIX.
