Add a .dir-locals.el file to configure emacs

.dir-locals.el

@@ -0,0 +1,7 @@
+((nil . ((indent-tabs-mode . nil)
+         (tab-width . 4)
+         (fill-column . 100)))
+ (c-mode . ((c-file-style . "k&r")
+            (c-basic-offset . 4)))
+ ((nil . ((truncate-lines . t)))
+          (text-mode . ((eval . ((turn-on-auto-fill)))))))