source/signal: Implement
diff --git a/.gitignore b/.gitignore
index 9b8c3e2..3c5419c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -51,4 +51,5 @@
 /test/source_base
 /test/source_event
 /test/source_io
+/test/source_signal
 /test/source_time