lib/Tools/usedir

--- a/lib/Tools/usedir	Tue Oct 21 20:17:40 2008 +0200
+++ b/lib/Tools/usedir	Tue Oct 21 20:18:07 2008 +0200
@@ -13,7 +13,7 @@
 function usage()
 {
   echo
-  echo "Usage: $PRG [OPTIONS] LOGIC NAME"
+  echo "Usage: isabelle $PRG [OPTIONS] LOGIC NAME"
   echo
   echo "  Options are:"
   echo "    -C BOOL      copy existing document directory to -D PATH (default true)"