Unify getting a count into single function

include/extern.h

@@ -204,6 +204,7 @@ E int FDECL(isok, (int, int));
 E int FDECL(get_adjacent_loc,
             (const char *, const char *, XCHAR_P, XCHAR_P, coord *));
 E const char *FDECL(click_to_cmd, (int, int, int));
+E char FDECL(get_count, (char *, char, long, long *));
 #ifdef HANGUPHANDLING
 E void FDECL(hangup, (int));
 E void NDECL(end_of_input);