Enter the following scrpit: SEE ATTACHED PHOTO

Test the script.

Make the following improvements to the script:

Validate inputs $($from reads$)$ to make sure that valid input was entered. If invalid input was entered, give them a message and ask them to enter it again. Considerations include:

allow user to enter a $"$y$"$ or "Yes" or "YES" or other valid answers to run the script $($pretest loop sentinel$)$

the year of birth in $4$ digits always start with $19$ or $20$

the number of months is $1$ to $12$ only

Change the script to allow the user to use long names for months

Add the number of days in age $($so you report the number of years, months, and days of age$)$ to the script

TO HAND IN: Take a screen shot of your entire script and a sample run for PART $1$

PART $2$: Experiment with managing processes using the process status command, including starting and stopping processes:

test the following commands and review their results

ps

ps $-$u

ps $$f

ps $$ef

ps $$l

ps ax

ps f

ps u

notice all of the fields with the different switches but specifically the PPID and PID. What are the differences between the different options?

create the following script using vi named looper:

#$!/$bin$/$bash

COUNT$=0$

for $(($ ; ; $))$

do

COUNT$=`$expr $COUNT $+1`$ #Notice the backtick does command substitution

echo $$The current loop count is : $$ $COUNT

echo $\text{'}$ CRTL$-$C to stop!$\text{'}$ #Notice single verses double quotes

done

$4.$ make the script executable with the chmod command

$5.$ copy the script to looper$2$ using the cp command

$6.$ execute the above $2$ scripts individually and watch them run $($example: $./$looper $)$

$7.$ rerun them a second time and CRTL$/$C and CRTL$/$Z during their execution

$8.$ use the ps command to see their status: ps u would be my choice, what is yours?

$9.$ TO HAND IN: Take a screen shot for PART $2$

$10.$ review the processes utilizing the top command, utilize some of the interactive commands for top,

notice which processes are getting the most system resources $($CPU & memory$)$

$11.$ kill the processes that are no longer running $($Stopped or Zombied$)$ using the kill $-9$ command

notice the Process states: Process.States.PNGDownload Process.States.PNG

PART $3$: Experiment with starting processes in the background, managing those processes, and changing the priority:

remove the echo commands from the looper script

start this script in the background by using the & $($example: $./$looper & $)$

use the jobs $($note the job ID with the jobs command$)$ and ps

move it to the foreground using the fg command followed by the job number, use CRTL$/$Z to stop it and return it to the background using the bg command and then kill the process.

TO HAND IN: Take a screen shot of the last $10$ commands in your history for PART $3$

change the priority level of a process

run your looper$2$ script in the background and note the NICE and PRI levels using the ps $$l command

issue a renice $+15$ PID and notice the results

start a process with nice $$n $19$ with your command $($maybe a looper script$),$ notice the results

clean up all of your Zombied and Stopped processes

PART $4$: Practice using redirection and pipes:

Develop a single command line using grouping, pipes and redirection to store records in a file $($named no$\_$of$\_$my$\_$processes$)$ that contains: date and time; the number of your user processes currently running on the general.

TO HAND IN: Take a screen shot of the last this command line for PART $4$