Function multicall_applet 

pub fn multicall_applet<'a>(
    argv0: &'a str,
    name: &str,
    bin: Option<&str>,
) -> Option<&'a str>

The applet name to parse as the first word, when argv[0] is not the dispatcher.

None means a dispatcher invocation (busybox ls): skip argv[0] and parse the rest. Some is a symlink invocation (ls -l): inject the basename.