Specifies that a non-varargs function binding will call a variadic C function with the specified number of fixed arguments. Platforms that pass variadic arguments differently than fixed arguments will need this annotation if the Java binding does not itself use varargs. Without Java varargs or this annotation, there's no way for jnr-ffi to know where fixed args end and variadic arguments begin, causing them all to be passed the way fixed arguments get passed on the given platform. See https://github.com/jnr/jnr-ffi/pull/292