What causes "-merge parameter must be less than 48.\n" in DrKLO/Telegram?

Use a merge value between 1 and 48 inclusive.

-merge parameter must be less than 48.\n

Error message

-merge parameter must be less than 48.\n

What it means

The -merge value exceeds the tool's fixed buffer capacity. The packets, len, and rng arrays are all declared with 48 elements (lines 62-64). The check `merge > 48` rejects values of 49 and above. Note: the error message says 'less than 48' but merge=48 is actually accepted (indices 0 through 47); the message is slightly misleading — it should say 'at most 48'.

Source

Thrown at TMessagesProj/jni/opus/src/repacketizer_demo.c:86

   if (argc < 3)
   {
      usage(argv[0]);
      return EXIT_FAILURE;
   }
   for (i=1;i<argc-2;i++)
   {
      if (strcmp(argv[i], "-merge")==0)
      {
         merge = atoi(argv[i+1]);
         if(merge<1)
         {
            fprintf(stderr, "-merge parameter must be at least 1.\n");
            return EXIT_FAILURE;
         }
         if(merge>48)
         {
            fprintf(stderr, "-merge parameter must be less than 48.\n");
            return EXIT_FAILURE;
         }
         i++;
      } else if (strcmp(argv[i], "-split")==0)
         split = 1;
      else
      {
         fprintf(stderr, "Unknown option: %s\n", argv[i]);
         usage(argv[0]);
         return EXIT_FAILURE;
      }
   }
   fin = fopen(argv[argc-2], "r");
   if(fin==NULL)
   {
     fprintf(stderr, "Error opening input file: %s\n", argv[argc-2]);
     return EXIT_FAILURE;
   }

View on GitHub (pinned to 45ab8f4308)

Solutions

Use a merge value between 1 and 48 inclusive.
If you need to process more than 48 packets at once, run the tool in multiple passes and concatenate the outputs.

Example fix

// before
repacketizer_demo -merge 100 in.oct out.oct
// after
repacketizer_demo -merge 48 in.oct out.oct

Defensive patterns

Strategy: validation

Validate before calling

int merge = atoi(arg);
if (merge > 48) {
    fprintf(stderr, "-merge parameter must be at most 48.\n");
    return EXIT_FAILURE;
}

Prevention

Remember the 48-packet buffer limit is hardcoded in the tool's array declarations.
For large batch operations, chain multiple repacketizer_demo invocations.

When it happens

Trigger: Passing `-merge 49` or any larger value. The check at line 84 fires when merge > 48.

Common situations: Attempting to batch a large number of packets; copy-paste from documentation that suggested a higher count; misunderstanding the buffer limit.

Related errors

AI-assisted analysis of DrKLO/Telegram@45ab8f4308 (2026-08-14). Data as JSON: /api/errors/e6c14eefcca70edc. Report an issue: GitHub.