sysinop

#!/bin/bash
####################################################################
# Sathish Arthar (Sathisharthar {at} gmail.com) - Jan 2014
####################################################################
#simple menu driven shell script to to get information about your Linux server / desktop and Do some Users and File operations Quickly.


# Define variables
LSB=/usr/bin/lsb_release

# Purpose: Display pause prompt
# $1-> Message (optional)
function pause(){
local message="$@"
[ -z $message ] && message="Press [Enter] key to continue..."
read -p "$message" readEnterKey
}

# Purpose - Display a menu on screen
function show_menu(){
date
echo "---------------------------"
echo " Main Menu"
echo "---------------------------"
echo "1. Operating system info"
echo "2. Hostname and dns info"
echo "3. Network info"
echo "4. Who is online"
echo "5. Last logged in users"
echo "6. Free and used memory info"
echo "7. Get my ip address"
echo "8. My Disk Usage"
echo "9. Process Usage"
echo "10. Users Operations"
echo "11. File Operations"
echo "12. Exit"
}

# Purpose - Display header message
# $1 - message
function write_header(){
local h="$@"
echo "---------------------------------------------------------------"
echo " ${h}"
echo "---------------------------------------------------------------"
}

# Purpose - Get info about your operating system
function os_info(){
write_header " System information "
echo "Operating system : $(uname)"
[ -x $LSB ] && $LSB -a || echo "$LSB command is not insalled (set \$LSB variable)"
#pause "Press [Enter] key to continue..."
pause
}

# Purpose - Get info about host such as dns, IP, and hostname
function host_info(){
local dnsips=$(sed -e '/^$/d' /etc/resolv.conf | awk '{if (tolower($1)=="nameserver") print $2}')
write_header " Hostname and DNS information "
echo "Hostname : $(hostname -s)"
echo "DNS domain : $(hostname -d)"
echo "Fully qualified domain name : $(hostname -f)"
echo "Network address (IP) : $(hostname -i)"
echo "DNS name servers (DNS IP) : ${dnsips}"
pause
}

# Purpose - Network inferface and routing info
function net_info(){
devices=$(netstat -i | cut -d" " -f1 | egrep -v "^Kernel|Iface|lo")
write_header " Network information "
echo "Total network interfaces found : $(wc -w <<<${devices})"

echo "*** IP Addresses Information ***"
ip -4 address show

echo "***********************"
echo "*** Network routing ***"
echo "***********************"
netstat -nr

echo "**************************************"
echo "*** Interface traffic information ***"
echo "**************************************"
netstat -i

pause 
}

# Purpose - Display a list of users currently logged on 
# display a list of receltly loggged in users 
function user_info(){
local cmd="$1"
case "$cmd" in 
who) write_header " Who is online "; who -H; pause ;;
last) write_header " List of last logged in users "; last ; pause ;;
esac 
}

# Purpose - Display used and free memory info
function mem_info(){
write_header " Free and used memory "
free -m

echo "*********************************"
echo "*** Virtual memory statistics ***"
echo "*********************************"
vmstat
echo "***********************************"
echo "*** Top 5 memory eating process ***"
echo "***********************************" 
ps auxf | sort -nr -k 4 | head -5 
pause
}

# Purpose - Get Public IP address form your ISP
function ip_info(){
cmd='curl -s'
write_header " Public IP information "
ipservice=checkip.dyndns.org
pipecmd=(sed -e 's/.*Current IP Address: //' -e 's/<.*$//') #using brackets to use it as an array and avoid need of scaping
$cmd "$ipservice" | "${pipecmd[@]}"
pause
}

# purpose - Get Disk Usage Information
function disk_info() {
usep=$(echo $output | awk '{ print $1}' | cut -d'%' -f1)
  partition=$(echo $output | awk '{print $2}')
write_header " Disk Usage Info"
if [ "$EXCLUDE_LIST" != "" ] ; then
  df -H | grep -vE "^Filesystem|tmpfs|cdrom|${EXCLUDE_LIST}" | awk '{print $5 " " $6}'
else
  df -H | grep -vE "^Filesystem|tmpfs|cdrom" | awk '{print $5 " " $6}'
fi
pause
}
#Purpose of Process Usage Information

function proc_info() {
write_header " Process Usage Info"
txtred=$(tput setaf 1)
txtgrn=$(tput setaf 2)
txtylw=$(tput setaf 3)
txtblu=$(tput setaf 4)
txtpur=$(tput setaf 5)
txtcyn=$(tput setaf 6)
txtrst=$(tput sgr0)
COLUMNS=$(tput cols)

center() {
	w=$(( $COLUMNS / 2 - 20 ))
	while IFS= read -r line
	do
		printf "%${w}s %s\n" ' ' "$line"
	done
}

centerwide() {
	w=$(( $COLUMNS / 2 - 30 ))
	while IFS= read -r line
	do
		printf "%${w}s %s\n" ' ' "$line"
	done
}

while :
do

clear

echo ""
echo ""
echo "${txtcyn}(please enter the number of your selection below)${txtrst}" | centerwide
echo ""
echo "1.  Show all processes" | center
echo "2.  Kill a process" | center
echo "3.  Bring up top" | center 
echo "4.  ${txtpur}Return to Main Menu${txtrst}" | center
echo "5.  ${txtred}Shut down${txtrst}" | center
echo ""

read processmenuchoice
case $processmenuchoice in

1 )
	clear && echo "" && echo "${txtcyn}(press ENTER or use arrow keys to scroll list, press Q to return to menu)${txtrst}" | centerwide && read
	ps -ef | less
;;

2 )
	clear && echo "" && echo "Please enter the PID of the process you would like to kill:" | centerwide
	read pidtokill
	kill -2 $pidtokill && echo "${txtgrn}Process terminated successfully.${txtrst}" | center || echo "${txtred}Process failed to terminate. Please check the PID and try again.${txtrst}" | centerwide
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

3 )
	top
;;

4 )
	clear && echo "" && echo "Are you sure you want to return to the main menu? ${txtcyn}y/n${txtrst}" | centerwide && echo ""
	read exitays
	case $exitays in
		y | Y )
			clear && exit
		;;
		n | N )
			clear && echo "" && echo "Okay. Nevermind then." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
		* )
			clear && echo "" && echo "${txtred}Please make a valid selection.${txtrst}" | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
	esac
;;

5 )
	clear && echo "" && echo "Are you sure you want to shut down? ${txtcyn}y/n${txtrst}" | centerwide && echo ""
	read shutdownays
	case $shutdownays in
		y | Y )
			clear && shutdown -h now
		;;
		n | N )
			clear && echo "" && echo "Okay. Nevermind then." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
		* )
			clear && echo "" && echo "${txtred}Please make a valid selection." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
	esac
;;

* )
	clear && echo "" && echo "${txtred}Please make a valid selection." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
;;
esac

done
pause
}

#Purpose - For getting  User operation and infrmations
function user_infos() {

write_header "User Operations"

txtred=$(tput setaf 1)
txtgrn=$(tput setaf 2)
txtylw=$(tput setaf 3)
txtblu=$(tput setaf 4)
txtpur=$(tput setaf 5)
txtcyn=$(tput setaf 6)
txtrst=$(tput sgr0)
COLUMNS=$(tput cols)

center() {
	w=$(( $COLUMNS / 2 - 20 ))
	while IFS= read -r line
	do
		printf "%${w}s %s\n" ' ' "$line"
	done
}

centerwide() {
	w=$(( $COLUMNS / 2 - 30 ))
	while IFS= read -r line
	do
		printf "%${w}s %s\n" ' ' "$line"
	done
}

while :
do

clear

echo ""
echo ""
echo "${txtcyn}(please enter the number of your selection below)${txtrst}" | centerwide
echo ""
echo "1.  Create a user" | center
echo "2.  Change the group for a user" | center
echo "3.  Create a group" | center
echo "4.  Delete a user" | center
echo "5.  Change a password" | center
echo "6.  ${txtpur}Return to Main Menu${txtrst}" | center
echo "7.  ${txtred}Shut down${txtrst}" | center
echo ""

read usermenuchoice
case $usermenuchoice in

1 )
	clear && echo "" && echo "Please enter the new username below:  ${txtcyn}(NO SPACES OR SPECIAL CHARACTERS!)${txtrst}" | centerwide && echo ""
	read newusername
	echo "" && echo "Please enter a group for the new user:  ${txtcyn}(STILL NO SPACES OR SPECIAL CHARACTERS!)${txtrst}" | centerwide && echo ""
	read newusergroup
	echo "" && echo "What is the new user's full name?  ${txtcyn}(YOU CAN USE SPACES HERE IF YOU WANT!)${txtrst}" | centerwide && echo ""
	read newuserfullname
	echo "" && echo ""
	groupadd $newusergroup
	useradd -g $newusergroup -c "$newuserfullname" $newusername && echo "${txtgrn}New user $newusername created successfully.${txtrst}" | center || echo "${txtred}Could not create new user.${txtrst}" | center
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center
	read
;;

2 )
	clear && echo "" && echo "Which user needs to be in a different group? ${txtcyn}(USER MUST EXIST!)${txtrst}" | centerwide && echo ""
	read usermoduser
	echo "" && echo "What should be the new group for this user?  ${txtcyn}(NO SPACES OR SPECIAL CHARACTERS!)${txtrst}" | centerwide && echo ""
	read usermodgroup
	echo "" && echo ""
	groupadd $usermodgroup
	usermod -g $usermodgroup $usermoduser && echo "${txtgrn}User $usermoduser added to group $usermodgroup successfully.${txtrst}" | center || echo "${txtred}Could not add user to group. Please check if user exists.${txtrst}" | centerwide
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center
	read
;;

3 )
	clear && echo "" && echo "Please enter a name for the new group below:  ${txtcyn}(NO SPACES OR SPECIAL CHARACTERS!)${txtrst}" | centerwide && echo ""
	read newgroup
	echo "" && echo ""
	groupadd $newgroup && echo "${txtgrn}Group $newgroup created successfully.${txtrst}" | center || echo "${txtred}Failed to create group. Please check if group already exists.${txtrst}" | centerwide
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center
	read
;;

4 )
	clear && echo "" && echo "Please enter the username to be deleted below:  ${txtcyn}(THIS CANNOT BE UNDONE!)${txtrst}" | centerwide && echo ""
	read deletethisuser
	echo "" && echo "${txtred}ARE YOU ABSOLUTELY SURE YOU WANT TO DELETE THIS USER? SERIOUSLY, THIS CANNOT BE UNDONE! ${txtcyn}y/n${txtrst}" | centerwide
	read deleteuserays
	echo "" && echo ""
	case $deleteuserays in
		y | Y )
			userdel $deletethisuser && echo "${txtgrn}User $deletethisuser deleted successfully." | center || echo "${txtred}Failed to delete user. Please check username and try again.${txtrst}" | centerwide
		;;
		n | N )
			echo "Okay. Nevermind then." | center
		;;
		* )
			echo "${txtred}Please make a valid selection.${txtrst}" | center
		;;
	esac
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center
	read
;;

5 )
	clear && echo "" && echo "Which user's password should be changed?" | centerwide
	read passuser
	echo ""
	passwd $passuser && echo "${txtgrn}Password for $passuser changed successfully.${txtrst}" | center || echo "${txtred}Failed to change password.${txtrst}" | center
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center
	read
;;

6 )
	clear && echo "" && echo "Are you sure you want to return to the main menu? ${txtcyn}y/n${txtrst}" | centerwide && echo ""
	read exitays
	case $exitays in
		y | Y )
			clear && exit
		;;
		n | N )
			clear && echo "" && echo "Okay. Nevermind then." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
		* )
			clear && echo "" && echo "${txtred}Please make a valid selection.${txtrst}" | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
	esac
;;

7 )
	clear && echo "" && echo "Are you sure you want to shut down? ${txtcyn}y/n${txtrst}" | centerwide && echo ""
	read shutdownays
	case $shutdownays in
		y | Y )
			clear && shutdown -h now
		;;
		n | N )
			clear && echo "" && echo "Okay. Nevermind then." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
		* )
			clear && echo "" && echo "${txtred}Please make a valid selection.${txtrst}" | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
	esac
;;

* )
	clear && echo "" && echo "${txtred}Please make a valid selection.${txtrst}" | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
;;

esac

done
pause
}

#Purpose  - For File Opertios
function file_info() {
write_header "File OPerations"
txtred=$(tput setaf 1)
txtgrn=$(tput setaf 2)
txtylw=$(tput setaf 3)
txtblu=$(tput setaf 4)
txtpur=$(tput setaf 5)
txtcyn=$(tput setaf 6)
txtrst=$(tput sgr0)
COLUMNS=$(tput cols)

center() {
	w=$(( $COLUMNS / 2 - 20 ))
	while IFS= read -r line
	do
		printf "%${w}s %s\n" ' ' "$line"
	done
}

centerwide() {
	w=$(( $COLUMNS / 2 - 30 ))
	while IFS= read -r line
	do
		printf "%${w}s %s\n" ' ' "$line"
	done
}

while :
do

clear

echo ""
echo ""
echo "${txtcyn}(please enter the number of your selection below)${txtrst}" | centerwide
echo ""
echo "1.  Create a file" | center
echo "2.  Delete a file" | center
echo "3.  Create a directory" | center
echo "4.  Delete a directory" | center
echo "5.  Create a symbolic link" | center
echo "6.  Change ownership of a file" | center
echo "7.  Change permissions on a file" | center
echo "8.  Modify text within a file" | center
echo "9.  Compress a file" | center
echo "10. Decompress a file" | center
echo "11. ${txtpur}Return to main menu${txtrst}" | center
echo "12. ${txtred}Shut down${txtrst}" | center
echo ""

read mainmenuchoice
case $mainmenuchoice in

1 )
	clear && echo "" && echo "Current working directory:" | center && pwd | center
	echo "" && echo "Please enter the ${txtcyn}full path${txtrst} and filename for the new file:" | centerwide && echo ""
	echo "${txtcyn}(if file exists, it will be touched)${txtrst}" | center && echo ""
	read touchfile
	echo "" && echo ""
	touch $touchfile && echo "${txtgrn}File $touchfile touched successfully.${txtrst}" | centerwide || echo "${txtred}Touch failed. How did you even do that?${txtrst}" | center
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

2 )
	clear && echo "" && echo "Current working directory:" | center && pwd | center && echo "" && ls && echo ""
	echo "Please enter the ${txtcyn}full path${txtrst} and filename for the file to be deleted:" | centerwide && echo ""
	read rmfile
	echo "" && echo ""
	rm -i $rmfile && echo "${txtgrn}File removed successfully.${txtrst}" | center || echo "${txtred}File removal failed.${txtrst}" | center
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

3 )
	clear && echo "" && echo "Current working directory:" | center && pwd | center && echo "" && ls && echo ""
	echo "Please enter the ${txtcyn}full path${txtrst} for the directory to be created:" | centerwide && echo ""
	read mkdirdir
	echo "" && echo ""
	mkdir $mkdirdir && echo "${txtgrn}Directory $mkdirdir created successfully.${txtrst}" | centerwide || echo "${txtred}Failed to create directory.${txtrst}" | center
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

4 )
	clear && echo "" && echo "Current working directory:" | center && pwd | center && echo "" && ls && echo ""
	echo "Please enter the ${txtcyn}full path${txtrst} for the directory to be removed:  ${txtcyn}(MUST BE EMPTY!)${txtrst}" | centerwide && echo ""
	read rmdirdir
	echo "" && echo ""
	rmdir $rmdirdir && echo "${txtgrn}Directory $rmdirdir removed successfully.${txtrst}" | centerwide || echo "${txtred}Failed to remove directory. Please ensure directory is empty.${txtrst}" | centerwide
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

5 )
	clear && echo "" && echo "Please enter the input file for the symbolic link:  ${txtcyn}(FULL PATH!)${txtrst}" | centerwide && echo ""
	read symlinfile
	echo "" && echo "Please enter the output file for the symbolic link:  ${txtcyn}(SERIOUSLY, FULL PATH!)${txtrst}" | centerwide && echo ""
	read symloutfile
	echo "" && echo ""
	ln -s $symlinfile $symloutfile
	cat $symloutfile && clear && echo "" && echo "${txtgrn}Symbolic link created successfully at $symloutfile${txtrst}" | centerwide || echo "${txtred}Failed to create symbolic link. Please check paths and filenames and try again.${txtrst}" | centerwide && rm -f $symloutfile
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

6 )
	clear && echo "" && echo "Which file's ownership should be changed?  ${txtcyn}(MUST EXIST, USE FULL PATH!)${txtrst}" | centerwide && echo ""
	read chownfile
	echo "" && echo "Please enter the username for the new owner of $chownfile:  ${txtcyn}(USER MUST EXIST)${txtrst}" | centerwide && echo ""
	read chownuser
	echo "" && echo "Please enter the new group for $chownfile:  ${txtcyn}(GROUP MUST EXIST)${txtrst}" | centerwide && echo ""
	read chowngroup
	echo "" && echo ""
	chown $chownuser.$chowngroup $chownfile && echo "${txtgrn}Ownership of $chownfile changed successfully.${txtrst}" | centerwide || echo "${txtred}Failed to change ownership. Please check if user, group and file exist.${txtrst}" | center
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

7 )
	clear && echo "" && echo "Which file's permissions should be changed?  ${txtcyn}(MUST EXIST, USE FULL PATH!)${txtrst}" | centerwide && echo ""
	read chmodfile
	echo "" && echo "Please enter the three-digit numeric string for the permissions you would like to set:" | centerwide
	echo ""
	echo "${txtcyn}( format is [owner][group][all]  |  ex: ${txtrst}777${txtcyn} for full control for everyone )${txtrst}" | centerwide
	echo ""
	echo "${txtcyn}4 = read${txtrst}" | center
	echo "${txtcyn}2 = write${txtrst}" | center
	echo "${txtcyn}1 = execute${txtrst}" | center
	echo ""
	read chmodnum
	echo "" && echo ""
	chmod $chmodnum $chmodfile && echo "${txtgrn}Permissions for $chmodfile changed successfully.${txtrst}" | centerwide || echo "${txtred}Failed to set permissions.${txtrst}" | center
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

8 )
	clear && echo "" && echo "Please enter the full path and filename for the file you wish to edit:" | centerwide && echo ""
	read editfile
	echo "Which program would you like to use to edit this file?" | centerwide && echo ""
	echo "${txtcyn}(please enter the number of your selection below)${txtrst}" | centerwide
	echo "1. vim" | center
	echo "2. nano" | center
	echo "3. mcedit" | center
	echo "4. emacs" | center
	echo "5. pico" | center
	echo ""
	read editapp
	echo ""
	case $editapp in
		1 )
			vim $editfile || echo "${txtred}Failed to open vim. Please check if it is installed.${txtrst}" | centerwide
		;;
		
		2 )
			nano $editfile || echo "${txtred}Failed to open nano. Please check if it is installed.${txtrst}" | centerwide
		;;

		3 )
			mcedit $editfile || echo "${txtred}Failed to open mcedit. Please check if it is installed.${txtrst}" | centerwide
		;;

		4 )
			emacs $editfile || echo "${txtred}Failed to open emacs. Please check if it is installed.${txtrst}" | centerwide
		;;

		5 )
			pico $editfile || echo "${txtred}Failed to open pico. Please check if it is installed.${txtrst}" | centerwide
		;;

		* )
			echo "${txtred}Please make a valid selection.${txtrst}" | center
		;;
	esac
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

9 ) 
	clear && echo "" && echo "Please enter the ${txtcyn}full path${txtrst} and filename for the file you wish to compress:" | centerwide && echo ""
	read pressfile
	echo "" && echo "Which method of compression would you like to use?" | centerwide && echo ""
	echo "${txtcyn}(please enter the number of your selection below)${txtrst}" | centerwide
	echo ""
	echo "1. gzip" | center
	echo "2. bzip2" | center
	echo "3. compress" | center
	echo ""
	read pressmethod
	echo ""
	case $pressmethod in
		1 )
			gzip $pressfile && echo "${txtgrn}File compressed successfully.${txtrst}" | center || echo "${txtred}File failed to compress.${txtrst}" | center
		;;

		2 )
			bzip2 $pressfile && echo "${txtgrn}File compressed successfully.${txtrst}" | center || echo "${txtred}File failed to compress.${txtrst}" | center
		;;

		3 )
			compress $pressfile && echo "${txtgrn}File compressed successfully.${txtrst}" | center || echo "${txtred}File failed to compress.${txtrst}" | center
		;;

		* )
			echo "${txtred}Please make a valid selection.${txtrst}" | center
		;;
	esac
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

10 )
	clear && echo "" && echo "Please enter the ${txtcyn}full path${txtrst} and filename for the file you wish to decompress:" | centerwide && echo ""
	read depressfile
	case $depressfile in
		*.gz | *.GZ )
			gunzip $depressfiles && echo "${txtgrn}File decompressed successfully.${txtrst}" | center || echo "${txtred}File failed to decompress.${txtrst}" | center
		;;

		*.bz2 | *.BZ2 )
			bunzip2 $depressfile && echo "${txtgrn}File decompressed successfully.${txtrst}" | center || echo "${txtred}File failed to decompress.${txtrst}" | center
		;;
		
		*.z | *.Z )
			uncompress $depressfile && echo "${txtgrn}File decompressed successfully.${txtrst}" | center || echo "${txtred}File failed to decompress.${txtrst}" | center
		;;
		
		* )
			echo "${txtred}File does not appear to use a valid compression method (gzip, bzip2, or compress). Please decompress manually.${txtrst}" | centerwide
	esac
	echo "" && echo "${txtcyn}(press ENTER to continue)${txtrst}" | center && read
;;

11 )
	clear && echo "" && echo "Are you sure you want to return to the main menu? ${txtcyn}y/n${txtrst}" | centerwide && echo ""
	read exitays
	case $exitays in
		y | Y )
			clear && exit
		;;
		n | N )
			clear && echo "" && echo "Okay. Nevermind then." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
		* )
			clear && echo "" && echo "${txtred}Please make a valid selection.${txtrst}" | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
	esac
;;

12 )
	clear && echo "" && echo "Are you sure you want to shut down? ${txtcyn}y/n${txtrst}" | centerwide && echo ""
	read shutdownays
	case $shutdownays in
		y | Y )
			clear && shutdown -h now
		;;
		n | N )
			clear && echo "" && echo "Okay. Nevermind then." | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
		* )
			clear && echo "" && echo "${txtred}Please make a valid selection.${txtrst}" | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
		;;
	esac
;;

* )
	clear && echo "" && echo "${txtred}Please make a valid selection.${txtrst}" | center && echo "" && echo "${txtcyn}(Press ENTER to continue.)${txtrst}" | center && read
;;

esac

done
pause
}
# Purpose - Get input via the keyboard and make a decision using case..esac 
function read_input(){
local c
read -p "Enter your choice [ 1 -12 ] " c
case $c in
1) os_info ;;
2) host_info ;;
3) net_info ;;
4) user_info "who" ;;
5) user_info "last" ;;
6) mem_info ;;
7) ip_info ;;
8) disk_info ;;
9) proc_info ;;
10) user_infos ;;
11) file_info ;;
12) echo "Bye!"; exit 0 ;;
*) 
echo "Please select between 1 to 12 choice only."
pause
esac
}

# ignore CTRL+C, CTRL+Z and quit singles using the trap
trap '' SIGINT SIGQUIT SIGTSTP

# main logic
while true
do
clear
show_menu # display memu
read_input # wait for user input
done