Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|diff -NrU3 dwm-5.1/dwm.c dwm-5.1.playground-pertag/dwm.c
|--- dwm-5.1/dwm.c	2008-07-29 20:18:32.000000000 +0200
|+++ dwm-5.1-pertag/dwm.c	2008-08-01 18:46:49.000000000 +0200
--------------------------
Patching file dwm.c using Plan A...
Hunk #1 succeeded at 238.
Hunk #2 succeeded at 1312.
Hunk #3 succeeded at 1329.
Hunk #4 succeeded at 1378.
Hunk #5 succeeded at 1499.
Hunk #6 succeeded at 1528.
Hunk #7 succeeded at 1697.
done