Use a subrange of all arguments in a Bash function

Question

I have this function in a Bash script:

comp() {
    rsync -v --archive $1/ $TMP/$2 $3 $4 $5 $6 $7 $8 $9
}

As you can see, I'm doing something special with arguments $1 and $2. Then I hackily just append all the rest of them to the end of the command. They go to $9, but in fact all should be appended.

There must be an easier way for this?

Note that anything above `$9` needs to appear in braces (e.g. `${10}`). — Jonah Bishop, Aug 30 '12 at 13:59

score 5 · Answer 1 · answered Aug 30 '12 at 14:17

You can use substring expansion, which might be useful in certain situations. For this, though, I must say I prefer Brian's solution of shifting, as it is a bit clearer. (Also, Brian's solution is POSIX; substring expansion is a bash extension.)

comp () {

    rsync -v --archive "$1"/ "$TMP/$2" "${@:3}"

}

score 4 · Answer 2 · answered Aug 30 '12 at 13:58

4

I wouldn't necessarily call it "easier," but you can do this:

comp() {
    archive=$1
    tempfile=$2
    shift 2
    rsync -v --archive $archive/ $TMP/$tempfile "$@"
}

That saves you from having to hard-code $3 through $11.

answered Aug 30 '12 at 13:58

Brian

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Use a subrange of all arguments in a Bash function

2 Answers2