Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|URL: http://dwm.suckless.org/patches/statusallmons
|This patch draws and updates the statusbar on all monitors.
|
|Index: dwm/dwm.c
|===================================================================
|--- dwm/dwm.c.orig
|+++ dwm/dwm.c
--------------------------
Patching file dwm.c using Plan A...
Hunk #1 succeeded at 715.
Hunk #2 succeeded at 1991.
done