Question

I want to call external application from shell script, but this shell script gets parameters (from other script) in a single variable. All was OK until I did not have to use double quotes for single parameter, but words separated by space.

Here is simplified example of my problem (sh_param just prints all passed parameters):

#!/bin/sh

pass() {
    echo "Result with \$@"
    ./sh_param $@
    echo "Result with \"\$@\""
    ./sh_param "$@"
    echo "Result with \$*"
    ./sh_param $*
    echo "Result with \"\$*\""
    ./sh_param "$*"
}

pass '"single param" separate params'

and results (sh_param just prints all passed parameters):

Result with $@
Param: "single
Param: param"
Param: separate
Param: params
Result with "$@"
Param: "single param" separate params
Result with $*
Param: "single
Param: param"
Param: separate
Param: params
Result with "$*"
Param: "single param" separate params

And I want:

Param: single param
Param: separate
Param: params

Answer 1

Answering my own question. BIG thanks goes to pzanoni.
xargs seems to parse correctly anything you are throwing to it 🙂
“$@”, “$“, $@ and $ works good with it. So my code now looks like:

#!/bin/sh

pass() {
    echo $* | xargs ./sh_param
}

pass '"single param" separate params'

And result is what I wanted:

Param: single param
Param: separate
Param: params