Bash multiple command line arguments

Question

I want to be able to run my script with one or more arguments and perform an action for all arguments passed.

So far, I have been able to run a command based on the first argument as follows:

#/bin/bash

ap=admin
lp=lender

if [[ "$1" = "ap" ]]; then
    echo "### pulling $ap ###"
elif [[ "$1" = "lp" ]]; then
    echo "### pulling $lp ###"
else 
echo "There is no service with that name"
fi

I want to be able to run my script with more than one argument as follows and run the commands needed for each of the arguments given. For example, if I run this:

./update.sh ap lp

I want to be able to detect both ap and lp and then execute the correct commands.

To summarise, if the person running the script passes 'ap' as the argument, I want to pull admin and if the user passes both 'ap' & 'lp' as the arguments, I want to pull both admin and lender.

Thanks in advance for your help!

Have a look here for a very readable, maintainable, extensible, standards-based approach... http://stackoverflow.com/a/16496491/2836621 — Mark Setchell, Nov 24 '15 at 12:21
Kudos, though, for actually checking the value of `$1`, rather than simply trying to execute whatever it happens to be with something like `"$1"` or `eval "$1"`. — chepner, Nov 24 '15 at 12:30

score 2 · Answer 1 · edited Nov 24 '15 at 12:31

2

Use a while loop to look through the arguments and use shift to move arguments $N+1 to $N. So after a shift the second argument becomes the first.

while [ "$#" -gt 0 ]
do
  if [[ $1 = "ap" ]]
  then
    echo "AP typed"
  elif [[ $1 = "lp" ]]
  then
    echo "LP typed"
  fi
  shift
done

edited Nov 24 '15 at 12:31

chepner

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answered Nov 24 '15 at 11:35

Neil Masson

2,609
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nautilor · Answer 2 · 2015-11-24T19:05:54.027

0

while [[ $# -gt 0 ]]
   do
       key="$1"
       case $key in
       ap)
               echo "### pulling $ap ###"

       ;;
       lp)
               echo "### pulling $lp ###"

       ;;
       *)
           echo "There is no service with that name"
       ;;
esac
shift
done

this will accept arguments in every order you put them

 $ ./update lp ap
 $ ./update ap lp
 $ ./update lp
 $ ./update ap

edited Nov 24 '15 at 19:05

answered Nov 24 '15 at 12:02

nautilor

106
12

You have too many shifts if `$1` matches an expected command. Either move the `shift` following the case statement to the `*` case, or remove the calls to `shift` from `ap` and `lp`. – chepner Nov 24 '15 at 14:42

Bash multiple command line arguments

2 Answers2