theta theta - 3 months ago 34
Bash Question

Process all arguments except the first one (in a bash script)

I have a simple script where the first argument is reserved for the filename, and all other optional arguments should be passed to other parts of the script.

Using Google I found this wiki, but it provided a literal example:

echo "${@: -1}"


I can't get anything else to work, like:

echo "${@:2}"


or

echo "${@:2,1}"


I get "Bad substitution" from the terminal.

What is the problem, and how can I process all but the first argument passed to a bash script?

Answer

Use this:

echo "${@:2}"

The following syntax:

echo "${*:2}"

would work as well, but is not recommended, because as @Gordon already explained, that using *, it runs all of the arguments together as a single argument with spaces, while @ preserves the breaks between them (even if some of the arguments themselves contain spaces). It doesn't make the difference with echo, but it matters for many other commands.