calling a script with options with spaces?

Springs · 04-15-2013, 04:50 AM

Hi All,

I'm using a "case" statement in a bash script which will let me select options which call particular functions.

My Question is that sometimes i need to pass it options with spaces which at the moment i'm wrapping "" around the words so they accept the spaces.

Is there another way to do this?

The way i call the whole script is:

./script OPTION1 OPTION2 OPTION3 etc..

Thanks

druuna · 04-15-2013, 05:29 AM

What do you mean by options with spaces?

Are you talking about multiple, individual options separated by a space (i.e.: --verbose --all) or an option that has a second part (i.e: --outfile file).

Although you can probably do this with a case statement (which might need the shift command, depending on your needs) I would suggest using bash's getopts

Here are a few links that might help:
- Small getopts tutorial
- Bash: parsing arguments with ‘getopts’
- Getopt and getopts

linosaurusroot · 04-15-2013, 05:31 AM

Double quotes around your variable is the right way to do this.

Code:

case "$banana" in
thing) do_1;;
otherthing) do_2;;
*) do_3;;
esac

konsolebox · 04-15-2013, 05:53 AM

So an example form of it is:

Code:

#!/bin/bash

CONFIG_OPT_A=false
CONFIG_OPT_B=false
CONFIG_OPT_W=false
CONFIG_OPT_W_ARG=''

while [[ $# -ge 1 ]]; do
    case "$1" in
    -a|--a-long-option)
        CONFIG_OPT_A=true
        ;;
    -b)
        CONFIG_OPT_B=true
        ;;
    -w|--with-arg)
        CONFIG_OPT_W=true
        if [[ -z $2 || <OPTIONALLY_TEST_$2_WITH_EXPRESSIONS> ]]; then
            echo "Invalid argument to option $1: $2"
            exit 1
        fi
        CONFIG_OPT_W_ARG=$2
        shift
        ;;
    *)
        echo "Unrecognized option: $1"
        exit 1
        ;;
    esac         
    shift
done

...

exit 0

Springs · 04-15-2013, 06:16 AM

Quote:

Originally Posted by linosaurusroot

Double quotes around your variable is the right way to do this.

Code:

case "$banana" in
thing) do_1;;
otherthing) do_2;;
*) do_3;;
esac

my script already has this setup with the "" around the variable but luckily that part is only single words.

The variable i pass to it afterwards will be the ones that have spaces.

Here is what i currently have to do:

./script variable1 "variable 2" "variable 3"

and what i would like to know if its possible to be able to call variable 2 and 3 etc without having to wrap them with "" each time.

konsolebox · 04-15-2013, 07:50 AM

@Springs It somehow confuses me what do you mean about a variable having a space. Do you mean the contents of the variable would have space, or the name of the variable itself would? Would you mind posting your script perhaps so that it would be clearer for us?

linuxguru1 · 04-19-2013, 09:31 AM

I think druuna is correct. If you are supplying arguments to a command on the command line your best bet is to use getopt(s). You must quote the arguments if there are spaces. Otherwise the shell will interpret spaces as a delimeter.

With that said, you could build your own version of getopt(s) with a case statement and 'shift' accordingly.

For example,
./script variable1 "variable 2" "variable 3"

case "$banana" in
variable1) # Do something ;;
variable) if [ $variable = 2 ] ; then # Do something ; fi
if [ $variable = 3 ] ; then # Do something ; fi ;;
*) ...
esac