download_status.c

#include "stdio.h"
#include "stdlib.h"

long int parse()
{
  long int bytes;
  char str[4096];
  int indexes[10];
  char* c;
  FILE* f = fopen( "output", "r");
  c = str;
  while((*(c++) = getc(f)) != EOF); c--;
  sscanf( str, "%ld", &bytes);
  return bytes;
}

//
// Run by ./a.out fname
// Shows the file size difference with time. Simple!
// You can also check if a download is completed or not
//
int main( int argc, char** argv)
{
  char command[4096];
  long int bytes1, bytes2;
  float mbps;
  float avgmbps = 0;

  sprintf( command, "stat --printf=%cs %s > output", '%',argv[1]);

  int i;
  for(i = 0; i < 5; i++)
  {
      system(command);
      bytes1 = parse();
      system("rm output");

      sleep(1);

      system(command);
      bytes2 = parse();
      system("rm output");

      mbps = (bytes2-bytes1) / 1e6;
      avgmbps += mbps;
      printf( "Current download rate of file %s = %f Mbytes/sec\n", argv[1], mbps);
  }

  printf( "5 second average = %f Mbytes/sec\n", avgmbps / 5.0);
  return 0;
}