Arrays of Arguments ("$@" vs "$*" Quoting Difference)

#!/bin/bash
set -- "first arg" "second arg"
count=0
for a in "$@"; do
    count=$((count + 1))
    echo "arg $count: [$a]"
done

#!/bin/bash
set -- "first arg" "second arg"
combined="$*"
echo "combined into one string: [$combined]"

#!/bin/bash
show_each() {
    for a in "$@"; do
        echo "received: [$a]"
    done
}

forward_args() {
    show_each "$@"
}

forward_args "has space" "nospace"

1. Assuming "$@" and "$*" behave the same; unquoted they're similar, but quoted they differ fundamentally.
2. Using $* (unquoted or quoted) to forward arguments to another command, which can merge or mis-split arguments containing spaces.
3. Forgetting "$@" expands to each positional parameter as its own separately-quoted word, which is almost always what you want when forwarding arguments.

• "$@" expands to each positional parameter as a separate, individually-quoted word — the safe default for forwarding arguments.
• "$*" expands to all positional parameters joined into a SINGLE string, separated by the first character of IFS.
• Unquoted $@ and $* behave almost identically (both split on whitespace), so the difference only really matters when quoted.
• Use "$@" when passing arguments through to another command; reserve "$*" for when you deliberately want one combined string.