Help Message for Shell Scripts
> $0 means a filename of a file that is being executed.<p>This is only a convention and is entirely up to the calling program.<p>For example in bash scripts you can use `exec -a name ...` to pass "name" as the 0th argument.<p>If you are already using #!/bin/bash you might as well use ${BASH_SOURCE[0]} to get the path to the current script.