steven@liquified:~% vi a
steven@liquified:~% vi b
steven@liquified:~% diff a b
1c1
< foobar
---
> foobaz
zsh: exit 1     diff a b
steven@liquified:~% diff -u a b
--- a   2006-07-08 22:29:11.000000000 +1000
+++ b   2006-07-08 22:29:16.000000000 +1000
@@ -1 +1 @@
-foobar
+foobaz
zsh: exit 1     diff -u a b