Redirecting loop output

You can redirect the loop output to a file using the done command:

#!/bin/bash 
for (( v1 = 1; v1 <= 5; v1++ )) 
do 
   echo "$v1" 
done > file 

If there is no file, it will be created and filled with the loop output.

This redirection is helpful when you don't need to show the loop output on the screen and save it to a file instead.

Controlling the loop

Having entered our loop, we may need to either exit the loop prematurely or perhaps exclude certain items from processing. If we want to process only directories in a listing, rather than every file of any type, then to implement this, we have loop control keywords, such as break and continue.

The break keyword is used to exit the loop, processing no more entries, whereas the continue keyword is used to stop the processing of the current entry in the loop and resume the processing with the next entry.

Assuming we only want to process directories, we could implement a test within the loop and determine the file type...