More work on streams

1 files changed, 23 insertions, 0 deletions

diff --git a/stdlib.pl b/stdlib.pl
index d093eed..c6b395f 100644
--- a/stdlib.pl
+++ b/stdlib.pl
@@ -110,6 +110,29 @@ open(SourceSink, Mode, Stream) :-
 close(StreamOrAlias) :-
 	close(StreamOrAlias, []).
 
+flush_output :-
+	current_output(S),
+	flush_output(S).
+
+stream_property(S, P) :-
+	stream_properties(Props),
+	member(prop(S,P), Props).
+
+at_end_of_stream :-
+	current_input(S),
+	stream_property(S, end_of_stream(E)),
+	!,
+	(E = at ; E = past).
+
+at_end_of_stream(S_or_a) :-
+	( atom(S_or_a)
+	-> stream_property(S, alias(S_or_a))
+	; S = S_or_a
+	),
+	stream_property(S, end_of_stream(E)),
+	!,
+	(E = at; E = past).
+
 % Standard exceptions
 
 instantiation_error :-