diff --git a/bitbake/lib/bb/ui/knotty.py b/bitbake/lib/bb/ui/knotty.py
index e1d42f7..2693a78 100644
--- a/bitbake/lib/bb/ui/knotty.py
+++ b/bitbake/lib/bb/ui/knotty.py
@@ -296,4 +296,9 @@ def main(server, eventHandler):
     if summary:
         print(summary)
 
+    if shutdown:
+        print("Execution was interrupted, returning a non-zero exit code.")
+        if return_value == 0:
+            return_value = 1
+
     return return_value