diff --git a/meson.build b/meson.build
index 55f9b47..d3d04f6 100644
--- a/meson.build
+++ b/meson.build
@@ -81,7 +81,7 @@
     'HOST_RUNNING_FILE', '/run/openbmc/host@{}-on')
 
 conf.set_quoted(
-    'CHASSIS_ON_FILE', '/run/openbmc/chassis@%d-on')
+    'CHASSIS_ON_FILE', '/run/openbmc/chassis@{}-on')
 
 configure_file(output: 'config.h', configuration: conf)