#! /bin/sh


#Shell script program that takes user input and displays information about the system.


#Prints choices to the console for the user to select.
echo "Choose and option from below:"
echo "1: Display information about the CPU"
echo "2: Display the interrupts on the system"
echo "3: Display the names of the output devices and the number of megabits read."
echo "4: Display the PID of a process that is running on the server and its status."
echo "-1: Exit"
echo



#Takes user input from the user.
read userInput


#While statement executes
while [ $userInput != "-1" ]
do


    echo "Choose an option from below:"
    echo "1: Display information about the CPU."
    echo "2: Display the interrupts on the system."
    echo "3: Display the names of the output devices and the number of megabits read."
    echo "4: Display the PID of a process that is running on the server and its status."
    echo "-1: Exit"
    read userInput #Takes input from the user.

    if [ $userInput = "1" ]
    then
        echo
        echo "***CPU Information***"
        cat /proc/cpuinfo
    elif [ $userInput = "2" ]
    then
        echo
        echo "***Interrupts Info***"
        cat /proc/interrupts
    elif [ $userInput = "3" ]
    then
        echo
        echo "***Names of output devices and number of megabits read***"
        cat /proc/diskstats
    elif [ $userInput = "4" ]
    then
        echo


        ps > info.txt #information about current proccesses running is redirected to the info.txt file.

        pidVar=`grep "bash" info.txt |  awk 'NR==2{ print $1}' info.txt` #Looks into the txt file for  the line that contains the  process called 'bash' and stores its process id into the pidVar to be used as a variable in the proc directory when searcing for information about the process.Furthermore the awk command combined with the 'NR==2' argument selects the first word in the second line of the document which is the process id of 'bash'.

                echo
                pidString="PID:"

                echo $pidString #Prints out PID string
        echo $pidVar #Prints out the process PID
        cat /proc/$pidVar/status | grep 'Name\|State' #Prints out lines that contain the words 'Name' and 'State'.
        echo

    elif [ $userInput = "-1" ] #Terminates the while loop.
    then
        echo "You have successfully exited the loop!"
        break
    fi



done