RE: [ns] "bad file size in video.dat"--why?

[Neundorf Alexander <Alexander.Neundorf.extern@icn.siemens.de>]

did you use the trace files from www-tkn.ee.tu-berlin.de/research/trace ?
Well, either the tcl script to convert them to the obscure binary format is broken or the tracetraffic.cc .

I hacked tracefile.cc to read a plain text format:

int TraceFile::setup()
{
   tracerec* t;
   struct stat buf;
   int i;
   FILE *fp;
   ofstream of("readlog");

   /* only open/read the file once (could be shared by multiple
    * SourceModel's
    */
   if (! status_)
   {
      status_ = 1;

      if (stat(name_, (struct stat *)&buf))
      {
         printf("could not stat %s\n", name_);
         return -1;
      }
      nrec_ = buf.st_size/sizeof(tracerec);
      unsigned nrecplus = nrec_ * sizeof(tracerec);
      unsigned bufst = buf.st_size;
      trace_ = new struct tracerec[nrec_];

      if ((fp = fopen(name_, "rb")) == NULL)
      {
         printf("can't open file %s\n", name_);
         return -1;
      }

      t = trace_;
      char buf[4*1024];
      while (!feof(fp)  )
      {

         if (fgets(buf,4*1024,fp)==0)
            break;
         if (sscanf(buf,"%d %d",&t->trec_time,&t->trec_size)!=2)
         {
            printf("read failed\n");
            return -1 ;
         };
         of<<t->trec_time<<" "<<t->trec_size<<endl;
         t++;
      };

   }
   /* pick a random starting place in the trace file */
   return (int(Random::uniform((double)nrec_)+.5));
}

and the tcl script:

#  puts -nonewline $trace_file_id [binary format "II" $time $length]
  puts $trace_file_id "$time $length"

I don't know why they used a binary format...

Bye
Alex

--
Free Dmitry Sklyarov ! 
http://www.freesklyarov.org

> -----Original Message-----
> From:	dongmin97 [SMTP:dongmin97@sina.com]
> Sent:	Wednesday, November 28, 2001 5:39 AM
> To:	ns-users@ISI.EDU
> Cc:	owner-ns-users@ISI.EDU
> Subject:	[ns] "bad file size in video.dat"--why?
> 
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