See the documentation for [Command::multicall][crate::Command::multicall] for rationale.

This example omits every command except true and false, which are the most trivial to implement,

$ busybox true
? 0

$ busybox false
? 1

Note: without the links setup, we can't demonstrate the multicall behavior

But includes the --install option as an example of why it can be useful for the main program to take arguments that aren't applet subcommands.

$ busybox --install
? failed
...

Though users must pass something:

$ busybox
? failed
Usage: busybox [OPTIONS] [APPLET]

APPLETS:
  true   does nothing successfully
  false  does nothing unsuccessfully
  help   Print this message or the help of the given subcommand(s)

Options:
      --install <install>  Install hardlinks for all subcommands in path
  -h, --help               Print help