The Computer Oracle

Check if any of the parameters to a bash script match a string

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Chapters
00:00 Check If Any Of The Parameters To A Bash Script Match A String
00:49 Answer 1 Score 5
01:20 Accepted Answer Score 91
01:46 Answer 3 Score 88
02:10 Answer 4 Score 10
02:45 Thank you

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Full question
https://superuser.com/questions/186272/c...

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Content licensed under CC BY-SA
https://meta.stackexchange.com/help/lice...

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Tags
#linux #unix #bash #shellscript

#avk47



ACCEPTED ANSWER

Score 91


It looks like you're doing option handling in a shell script. Here's the idiom for that:

#! /bin/sh -

# idiomatic parameter and option handling in sh
while test $# -gt 0
do
    case "$1" in
        --opt1) echo "option 1"
            ;;
        --opt2) echo "option 2"
            ;;
        --*) echo "bad option $1"
            ;;
        *) echo "argument $1"
            ;;
    esac
    shift
done

exit 0

(There are a couple of conventions for indenting the ;;, and some shells allow you to give the options as (--opt1), to help with brace matching, but this is the basic idea)




ANSWER 2

Score 88


This worked for me. It does exactly what you asked and nothing more (no option processing). Whether that's good or bad is an exercise for the poster :)

if [[ "$*" == *"YOURSTRING"* ]]
then
    echo "YES"
else
    echo "NO"
fi

This takes advantage of special handling of $* and bash super-test [[]] brackets.




ANSWER 3

Score 10


How about searching (with wildcards) the whole parameter space:

if [[ $@ == *'-disableVenusBld'* ]]
then

Edit: Ok, ok, so that wasn't a popular answer. How about this one, it's perfect!:

if [[ "${@#-disableVenusBld}" = "$@" ]]
then
    echo "Did not find disableVenusBld"
else
    echo "Found disableVenusBld"
fi

Edit2: Ok, ok, maybe this isn't perfect... Think it works only if -param is at the start of the list and will also match -paramXZY or -paramABC. I still think the original problem can be solved very nicely with bash string manipulation, but I haven't quite cracked it here... -Can you??




ANSWER 4

Score 5


disCopperBld=
for x; do
  if [ "$x" = "-disCopperBld" ]; then disCopperBld=1; break; fi
done
if [ -n "$disCopperBld" ]; then
  ...
fi

If you need to test only the parameters starting at $3, do the search in a function:

## Usage: search_trailing_parameters NEEDLE NUM "$@"
## Search NEEDLE amongst the parameters, skipping $1 through ${$NUM}.
search_trailing_parameters () {
  needle=$1
  shift $(($2 + 2))
  for x; do
    if [ "$x" = "$needle" ]; then return 0; fi
  done
  return 1
}
if search_trailing_parameters -disCopperBld 2 "$@"; then
  ...
fi

But I wonder why you're trying to do this in the first place, it's not a common need. Usually, you'd process options in order, as in Dennis's answer to your previous question.