diff -ru g1/f.txt g2/f.txt
--- g1/f.txt	2026-09-07 19:16:09.515858853 +0000
+++ g2/f.txt	2026-09-07 19:16:09.515858853 +0000
@@ -1 +1 @@
-a
+b
Seulement dans g1: onlyleft.txt
