How to Determine the Number of Files and Subdirectories in Linux

filesls

When displaying directories in Linux using ls -ld, I get something like this:

user@shell:~/somedirectory$ ls -ld 
drwxr-xr-x 2014 K-rock users 65536 20011-11-05 11:34
user@shell:~/somedirectory$

How would I find the number of subdirectories and files in the somedirectory using the result above? From what I understand, the number of links corresponds to the number of subdirectories, but what about the number of files? How would I read the result of the ls -ld to find those numbers?

Also, this is an assignment and I have to say the number of files and subdir that are in somedirectory using the result shown above. So I can't really use any other code unfortunately.

Best Answer

Since, you want to decipher from the output that you have got, we will try and simplify things. 

ls -ld
drwxr-xr-x 4 root root 4096 Nov 11 14:29 .

Now, ls -ld on a directory gives me the output as above. Now, the number 4 is something that you need to concentrate on. The 4 corresponds to:

  • the entry for that directory in its parent directory;
  • the directory's own entry for .;
  • the .. entries in the 2 sub-directories inside the directory.

To verify this, if I just issue ls I could see that I have couple of more directories. So, this gives an idea of what we could decipher from the output of your case.

drwxr-xr-x 2014 K-rock users 65536 20011-11-05 11:34

There are 2012 sub-directories inside which is why you get 2014 in the output.

As to the number of files, it is not possible to find it out from the output that you have.

To test if my theory is correct, I did the below testing. 

ls -la | grep -E '[d]' #Display only directories
drwxr-xr-x 12 root root 4096 Nov 11 14:42 .
drwxr-xr-x  4 root root 4096 Nov 11 14:20 ..
drwxr-xr-x  3 root root 4096 Nov 11 14:45 hello1
drwxr-xr-x  2 root root 4096 Nov 11 14:42 hello2
drwxr-xr-x  2 root root 4096 Nov 11 14:42 hello3
drwxr-xr-x  2 root root 4096 Nov 11 14:42 hello4
drwxr-xr-x  2 root root 4096 Nov 11 14:42 hello5
drwxr-xr-x  2 root root 4096 Nov 11 14:42 hello6
drwxr-xr-x  2 root root 4096 Nov 11 14:42 hello7
drwxr-xr-x  2 root root 4096 Nov 11 14:42 hello8
drwxr-xr-x  2 root root 4096 Nov 11 14:21 hello-subdir
drwxr-xr-x  2 root root 4096 Nov 11 14:29 spaced hello

Now, I issue ls -ld command and the output I get is,

ls -ld
drwxr-xr-x 12 root root 4096 Nov 11 14:42 .

It did not take into consideration the files or subdirectories nested inside the subdirectories of the folder. Basically, the above command says I have 10 directories inside my folder.

P.S.: It is often a bad idea to parse something from ls output as it is not reliable. Use find with -maxdepth instead if you have a chance to use it.

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