+/* Arrow keys are esc [ A to esc [ D */
+/* Alt keys are just esc then key (e.g. Alt-g is esc g ). */
+/* Ctrl (then letter) keys are just Dec 1 to Dec 26 */
+
+/* TO DO: Use the helper function range */
+/* ( range(rstart, rend, val). ) */
+/* to handle entire ranges at once. */
+
+
+void keyhandler(buf b)