Question

I am trying to write a script that mimics cp where there is a source and destination input. How can I count the number of arguments given on the command line?

For example:

./myscript src dest

How can I check that at least 2 things were given?

Answer 1

Use the $# special variable. Its value is the number of arguments. So if you have a script that contains only:

echo $#

and execute it like this:

thatscript foo bar baz quux

It’ll print 4.

In your case you may want to do something like:

if [ $# -lt 2 ]; then
    # TODO: print usage
    exit 1
fi