diff --git a/doc/intro.md b/doc/intro.md
index aed58cd4bd..51de7e5624 100644
--- a/doc/intro.md
+++ b/doc/intro.md
@@ -429,7 +429,7 @@ Basic block graphs
 ```
 af: Load function metadata
 ag $$ > a.dot: Dump basic block graph to file
-ag $$ | xdot: Show current function basic block graph
+ag $$ | xdot -: Show current function basic block graph
 ```
 Call graphs