Directory listing with for loop

Often had to check the files between directories if name matches or copy the missing ones, in cases of taking backup.

Most of the sites come up with the while loop, but i found us `for` loop

$ ls -l

total 1392

-rw-------@ 1 sanjeev  users  277935 May 17 18:21 Jenkins_Job_packaging.pdf

-rw-------@ 1 sanjeev  users  227774 May 17 18:21 Pipeline Based Alert and Notification.docx

-rw-r--r--@ 1 sanjeev  users    1324 May 17 18:21 SieveOfAtkin.js

-rw-r--r--  1 sanjeev  users    1301 May 17 18:21 VPN (Cisco IPSec).networkConnect

-rw-------@ 1 sanjeev  users  187319 May 17 18:21 algo.docx

-rw-r--r--  1 sanjeev  users    3797 May 17 18:21 bill.feb

-rw-r--r--  1 sanjeev  users      65 May 17 18:22 i

With for loop it was bad output

j=0

for i in `ls`; do

let j=j+1

echo "$j: $i"

done 

$ bash i

1: Jenkins_Job_packaging.pdf

2: Pipeline

3: Based

4: Alert

5: and

6: Notification.docx

7: SieveOfAtkin.js

8: VPN

9: (Cisco

10: IPSec).networkConnect

11: algo.docx

12: bill.feb

13: i

The spaces in filename is used as separators

$IFS
internal field separator
This variable determines how Bash recognizes fields, or word boundaries, when it interprets character strings.

Improved for loop, using IFS

IFS=$'\n'

j=0

for i in `ls`; do

let j=j+1

echo "$j: $i"

done 

And finally we get the correct filenames

$ bash i

1: Jenkins_Job_packaging.pdf

2: Pipeline Based Alert and Notification.docx

3: SieveOfAtkin.js

4: VPN (Cisco IPSec).networkConnect

5: algo.docx

6: bill.feb

7: i

Well IFS is well documented, but not popularly used .