LinuxQuestions.org - BASH scripts check for arguments

- Linux - Newbie (https://www.linuxquestions.org/questions/linux-newbie-8/)

- - BASH scripts check for arguments (https://www.linuxquestions.org/questions/linux-newbie-8/bash-scripts-check-for-arguments-793420/)

BASH scripts check for arguments

I know that $1 ... $n will set the argument to the values but what happened if I have many options in one scripts lets suppose.

I can run:
myscript -1stargument -2ndargument -3rdargument

or myscript -1stargument

or myscript -1stargument -3rdargument
.
.
.

In my scripts I have

if [ $1 = "-1stargument" -o $2 = "-2ndargument"] #for every isntruction i need

fi

but is there any wayu to do:
if [ (any arguments or commands) = "(mydesired option ] ; then
(do this...)

fi

?

Thanks

Code:

for argument in $@ ;do

  # case or if, for example:

  case $argument in

    "-1stargument" )

      do 1

    ;;

    "-2stargument" )

      do 2

    ;;

  esac

done

getopts is designed for option parsing. It's one of those things that is better learned by example than by reading the documentation. Here's my getopts template.
EDIT: corrected ANSI string usage (in red).

Code:

    # Set defaults that may be overriden by command line parsing

    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    <whatever>



    # Parse command line

    # ~~~~~~~~~~~~~~~~~~

    while getopts dhVo: opt 2>/dev/null

    do

        case $opt in

            d )

                debug='YES'

                ;;

            h )

                usage -v

                \exit 0

                ;;

            V )

                echo "$prgnam version $prg_ver"

                \exit 0

                ;;

            o )

                o_optarg="$OPTARG"

                ;;

            * )

                emsg="$emsg"$'\n'"<error message>"

        esac

    done



    # Test for extra arguments

    # ~~~~~~~~~~~~~~~~~~~~~~~~

    shift $(( $OPTIND-1 ))

    if [[ $* != '' ]]; then

        emsg="$emsg"$'\n'"<error message>"

    fi



    # Test for mandatory options not set

    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    if [[ ${o_optarg:-} = '' ]]; then

        <error message and exit>

    fi



    # Report any accumulated errors

    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    if [[ $emsg != '' ]]; then

        echo "$emsg" >&2

        usage

        \exit 1

    fi

Quote:

Originally Posted by troop (Post 3887095)

Code:

for argument in $@ ;do

Code:

for argument in "$@"; do

Has arguments quoted.....

Thank you to catkin for that post; I had thought about doing something similar, but it was one of many things that I never got around to.

If you want a tutorial, you could read here.

Quote:

Originally Posted by salasi (Post 3888197)

If you want a tutorial, you could read here.

Thanks salasi -- that's a good tutorial; bookmarked :)

Thanks! I will give it a try on Monday!