Function problem

Shell Programming and Scripting
1

hey guys, im trying to learn bourne shell atm and I'm having some issues with functions.

so heres my code:

#!/bin/bash

##functions

memory () {
free -m
}

space () {
    df -h
}


ip () {
    arp
}


user () {
    whoami
}



#'eingabemen�'

echo " hello how would you like to proceed? "
echo " 1) check memory "
echo " 2) check free space "
echo " 3) ip info "
echo " 4) user info "
echo " 5) nothing i'd just like to exit "

##read

read input;

case $input in 

    1)  echo " you've selected check memory..1 sec pls "
echo -e " free memory: " ; free -m;;
    2)  echo " you've selected check free space..1 sec pls "
echo -e " free space: " ; df -h;;
    3)  echo " you've selected ip info . 1 sec pls "
echo -e  " ipinfo: " ; ifconfig;;
    4)  echo " you've selected user info..1 sec pls "
echo -e " benutzer: " ; whoami;;
     5)  exit
esac

i came this far, :o now my problem is, i want to open my shell script by

for example and i want the function "space" which ive created to show me the info I need.

can anyone help me trying to fix this. thanks guys

2

Hello,

I think that you should launch your script in this way

./test.sh 2

or other number that do you want.

3

maybe I didnt write correctly and you missunderstood me, i'm sorry.
what i want to do is. when i open my script my normal menu appers. now i just want to make it quicker and enter the function after the test.sh path i already defined before and get my data.
greets

4

Hi,
your script defines some functions but never uses them. When you process the userinput you call some commands directly that you use in the functions .
About your problem: command line arguments are stored in the positional parameters. They are referenced by a number which reflects their position. The first argument is $1 , the second $2 ,... The special parameter $# holds the number of arguments passed.
I would check if $# is 1 and if that's true assign the corresponding number to the variable input depending on what $1 holds.

1 Like
5

If you want to get a value from the command line, use the positional parameters, $1, etc., not 'read'.

case $1 in 
    1|memory)  echo " you've selected check memory..1 sec pls "
               echo -e " free memory: " ; free -m;;
    2|space)  echo " you've selected check free space..1 sec pls "
              echo -e " free space: " ; df -h;;
    3|ipinfo)  echo " you've selected ip info . 1 sec pls "
               echo -e  " ipinfo: " ; ifconfig;;
    4|user)  echo " you've selected user info..1 sec pls "
             echo -e " benutzer: " ; whoami;;
     5|exit)  exit
esac
1 Like
6

You could try this:

#!/bin/sh
#
#	Vars & Functions
#
	MENU="memory space ip user"
	memory () {
		free -m
	}

	space () {
	    df -h
	}


	ip () {
	    arp
	}


	user () {
	    whoami
	}
#
#	Menu
#
	if [[ -z $1 ]]
	then	echo "Select which info to display"
		select ENTRY in $MENU;do break;done
	else	ENTRY=$1
	fi
#
#	Execute
#
	$ENTRY

Hope this helps

NOTE:
This only works as long as the menu entry to choose from is named identical as the function to execute

1 Like