A character vector containing the name of the executable and the
user-supplied command line arguments. The first element is the name
of the executable by which R was invoked. The exact form of this
element is platform dependent: it may be the fully qualified name, or
simply the last component (or basename) of the application, or for an
embedded R it can be anything the programmer supplied.
trailingOnly = TRUE, a character vector of those arguments
(if any) supplied after --args.