Need help to make a shell script with usage

Shell Programming and Scripting
1

Hello,

I begin to write my first shell script, but I am totally lost, hope you can help me.

I'd like to write a script with some conditions and multiples usages:

./myscript.sh -i <host>

or

./myscript.sh -e <host>

Have you some suggestion, because I am really lost, I try to do something with an echo and a read answer but it is not good.

If you have a good exemple I can adapt it's a good thing for me too.

2

With no indication of what conditions you are talking about, no indication of what you want the -i and -e options to do, and no indication of what you want the script to do with or without options; it is hard to make any useful suggestions.

3

Take a look at this post, where it shows parameters being passed.

4

Francesco, can you briefly explain what is your requirement?

5

you just need to search for

CASE

statement on google. I hope this is what you are looking for.

6

I must admit I am not very clear, please excuse me.

myscript.sh has differents usage

./myscript.sh -i <host>

==> will lauch an apt-get update on <$host>

./myscript.sh -e <host>

==> will launch an apt-get remove on <$host>

I have 6 hosts=

HOST='host1 host2 host3 host4 host5 host6'

I'd like to use fonction to execute the command, but all the exemple I saw are not very easy for me.

I'd like to have an usage:

./myscript.sh
Usage: myscript.sh {install -i host|remove -e host|}

Regards,

7 
if [ "$#" -eq 0 ]
then
        echo "Usage: myscript.sh {install -i host|remove -e host|}"
        exit 1
fi
8

Thanks Corona, but I know to do this part.

I just need advices to howto write my functions.

Regards

9

We can't write the whole thing for you.

What have you tried?

10

This is how my script begin. For the exemple and the exercice, I am trying to execute something with differents programs. As you see, I think something missing. Do I have to write a loop with a for i in ?

#!/bin/sh
PROGS='ntp apache mysql'

set -e

if [ "$#" -eq 0 ]
then
        echo "Usage: test.sh {install-i prog|remove-r prog}"
        exit 1
fi

install() {
     echo "so you want to install $PROGS? (y/n)"

     read reponse

     if [[ $reponse == "y" ]]
       then apt-get install $PROGS
     fi
}
11

Without knowing what you want to do, it's difficult to say how you should write your for-loop.

You can use $# to tell how many arguments are left, and shift to delete the first argument, so you can make a loop while $# is greater than zero and check the value of $1 every loop to determine what to do.

12

I want to install a program (ntp, apache or mysql) with a shell script. It is just an exercice for me, because I can install it without writing anything and just launch an apt-get install.

I want this usage:

./myscript.sh -install package name

or

./myscript.sh -remove package name

where package name are a variable located in my script.

I am sorry if it sounds confused, I cannot speack english very well and I am a beginner in shell programming.

13

Hello Francesco

You can use something like this.

cat test.sh

#!/bin/sh
while getopts ":n:a:m:" opt; do
  case $opt in
    n)
      installing command for ntp
      ;;
    a)
      installing command for apache
      ;;
    m)
      installing command for mysql
     ;;
    \?)
      echo "Invalid option: -$OPTARG" >&2
      ;;
  esac
done

How to run the script

./test.sh -a apache , ./test.sh -n ntp , ./test.sh -m mysql

This is the case if you want to remove or install the package one by one for ntp,apache or mysql..