Renamed path.cat to path.join.
diff --git a/Tools/scripts/which.py b/Tools/scripts/which.py
index b9b888b..b36c5ca 100755
--- a/Tools/scripts/which.py
+++ b/Tools/scripts/which.py
@@ -16,7 +16,7 @@
 for prog in sys.argv[1:]:
 	ident = ()
 	for dir in pathlist:
-		file = path.cat(dir, prog)
+		file = path.join(dir, prog)
 		try:
 			st = posix.stat(file)
 			if S_ISREG(st[ST_MODE]):