diff --git a/main.c b/main.c
index 4ebc5cf..23ea098 100644
--- a/main.c
+++ b/main.c
@@ -80,11 +80,11 @@ int old_c_main(int argc, char **argv)
         radio_list();
         exit(0);
     }
-    */
     if (read_flag + write_flag + config_flag + csv_flag + verify_flag > 1) {
         fprintf(stderr, "Only one of -r, -w, -c, -v or -u options is allowed.\n");
         usage();
     }
+    */
     setvbuf(stdout, 0, _IOLBF, 0);
     setvbuf(stderr, 0, _IOLBF, 0);
 
diff --git a/src/lib.rs b/src/lib.rs
index 164830c..b7e7511 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -72,11 +72,23 @@ pub extern "C" fn rust_main(argc: c_int, argv: *const *const c_char) -> c_int {
   };
 
   let list_flag = matches.opt_present("l");
+  let verify_flag = matches.opt_present("v");
+  let read_flag = matches.opt_present("r");
+  let write_flag = matches.opt_present("w");
+  let config_flag = matches.opt_present("c");
+  let csv_flag = matches.opt_present("u");
+
   if list_flag {
     radio::list();
     exit(0);
   }
 
+  if [read_flag, write_flag, config_flag, csv_flag, verify_flag].iter().filter(|x| **x).count() > 1 {
+    eprintln!("Only one of -r, -w, -c, -v or -u options is allowed.");
+    exit(-1);
+    //print_usage();
+  }
+
   unsafe {
     old_c_main(argc, argv)
   }