static UnixStream<String> echo(final String input){
  Objects.requireNonNull(input,"The input must not be null");
  return new UnixStreamImpl<>(Stream.of(input));
}

static UnixStream < String > echo ( final String input ) { Objects . requireNonNull ( input , "The input must not be null" ) ; return new UnixStreamImpl < > ( Stream . of ( input ) ) ; }
create a new unixstream with the given input .
