在bash中动态生成命令

Question

I want to dynamically generate pretty long bash command depending on the command line options. Here is what I tried:

CONFIG_PATH=""

#Reading CONFIG_PATH from getopts if supplied

SOME_OPT=""
if [ ! -z "$CONFIG_PATH" ]; then
    SOME_OPT="-v -s -cp $CONFIG_PATH"
fi

some_bash_command $SOME_OPT

The point here is that I want to pass 0 arguments to the some_bash_command if no arguments were passed to the script. In case there were some arguments I want to pass them.

It works fine, but the problem is that this approach looks rather unnatural to me.

What would be a better yet practical way to do this?

Answer 1

Your approach is more-or-less the standard one; the only significant improvement that I'd recommend is to use an array , so that you can properly quote the arguments. (Otherwise your command can horribly misbehave if any of the arguments happen to include special characters such as spaces or asterisks.)

So:

SOME_OPT=()
if [ ! -z "$CONFIG_PATH" ]; then
    SOME_OPT=(-v -s -cp "$CONFIG_PATH")
fi

some_bash_command "${SOME_OPT[@]}"