adds busy check before starting

bin/vcmp

@@ -323,6 +323,8 @@ def main():
     parser.add_argument('-n', '--nice', type=lambda x: int(x) if 0 <= int(x) <= 39 else exec('raise ValueError("Nice value must be between 0 and 39")'),
                       default=20,
                       help='Nice value for process priority (default: 20). Valid values are 0 (highest priority) to 39 (lowest priority). Lower values use more system resources.')
+    parser.add_argument('-i', '--ignore-busy', action='store_true',
+                      help='Ignore system busy check and run anyway')
     args = parser.parse_args()
 
     setup_logging(bool(args.verbose))
@@ -331,6 +333,10 @@ def main():
     destination_dir = args.destination_dir if args.destination_dir else args.source_dir
     temp_dir = args.temp_dir
 
+    if not args.ignore_busy and is_system_busy():
+        logging.error("System is busy, try again later or use --ignore-busy flag to override")
+        sys.exit(1)
+
     logging.info(f"Starting video compression from {source_dir} to {destination_dir}")
 
     global total_files