190. Which command is suitable to list out all the directories in the working directory, in linux/unix
environment?
A. 𝐼𝑠 − 1|𝑔𝑟𝑒𝑝 𝑑
⋀
B. 𝑔𝑟𝑒𝑝 𝑑
⋀
|𝐼𝑠 − 1
C. 𝐼𝑠 − 1|𝑔𝑟𝑒𝑝 𝑑
⋀
D. 𝐼𝑠|𝑔𝑟𝑒𝑝 𝑑𝑖�

Explanation:

To list only directories from the current working directory in a Unix/Linux shell, you can use:

Breakdown of the Command:

• ls -l:

  • Lists files and directories in long format (detailed view), where each line starts with the file type (d for directory, - for file, etc.)

• grep ^d:

  • Filters only the lines that start (^) with d, i.e., directories.

This way, only directories are listed from the output of ls -l.

Why Other Options Are Incorrect:

• B. grep d^ | ls -l: Incorrect syntax and reversed order – grep cannot pipe into ls.

• C. Repeats A: Appears to be a typo/duplicate.

• D. ls | grep dir: This command assumes directory names contain “dir,” which is not general or reliable.

Conclusion:

To reliably list only directories, the command:

is the most suitable.

Correct Answer: A. ls -l | grep ^d