UNIX Shell Scripting Bourne loop Question programming homework help

Description:

Write a shell script (to run on the Bourne shell) that runs an infinite loop to monitor the creation and removal of .pdf or .PDF files under the current directory. Every 3 seconds it should display a list of those filenames created or removed after the previous display. Without loss of practical significance of this utility, we can assume that the time interval between creation of a .PDF or .pdf file and removal of a .PDF or .pdf file is over 3 seconds, which means that it’s unnecessary for your script to handle the situation where creation of a file is followed by immediate removal of a file. (Hint: research the cmp and comm commands.) Your script for this task must be named tasktwo.sh. 

The following is a sample output of the script (It is OK that the script leaves behind a temporary file when it is finally interrupted):

No pdf files have been created or removed in the last 3 seconds.

No pdf files have been created or removed in the last 3 seconds.

The following pdf file(s) have been created in the last 3 seconds:

a3.pdf   a4.pdf   a5.pdf

The following pdf file(s) have been removed in the last 3 seconds:

a4.pdf   a5.pdf

No pdf files have been created or removed in the last 3 seconds.

No pdf files have been created or removed in the last 3 seconds.

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