/* read_3dot.c

   Tina Suen
   9-12-05
   12-21-05

   Example program to read 3.* files.
 
   - A line of data in the 3.* file consists of:
   ID     ID of ship/buoy
   year   year 
   month  month
   day    day
   hour   hour
   lat    latitude that observation corresponds to
   lon    longitude that observation corresponds to
   u      zonal wind speed
   v      meridional wind speed
   ta     air temperature
   qa     specific humidity
   sst    sea surface temperature 
   taux   zonal surface stress
   tauy   meridional surface stress
   shf    sensible heat flux
   lhf    latent heat flux 
   press  sea level pressure
   sd     swell direction
   wh     wave height

   All values at 10m except press, sst, sd, and wh.

*/


#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

typedef struct {
  char ID[8];
  int year;
  int month;
  int day;
  float hour;
  float lat, lon;
  float vars[12];

} DATA;


int main()
{
  //char InFile[] = "/Net/scratch1/winde/newwinds/3.moored2002";
  //char InFile[] = "/Net/scratch1/winde/newwinds/3.drifting2002";
  char InFile[] = "/Net/scratch1/winde/newwinds/3.VOS2002";

  DATA buf[200];
  int input;
  ssize_t nread;

  input = open(InFile, O_RDONLY);

  if ( !input )
  {
    printf( "Can't open file\n" );
    exit(1);
  }

  // Try to read 200 observations at a time.  Actual num read is nread.
  while ( (nread = read( input, &buf, sizeof(DATA)*200 )) > 0 ) 
  {
    int obs_read = nread / sizeof(DATA);
    int obs;

    // Loop through nread obs
    for ( obs = 0; obs < obs_read; ++obs ) 
    {
	// access to each obs here
	// ex:

      printf( "%s %d %d %d %f %f %f %f %f %f %f %f %f %f %f %f %f %f %f\n",
	      buf[obs].ID, buf[obs].year, buf[obs].month, buf[obs].day, buf[obs].hour, buf[obs].lat,
	      buf[obs].lon, buf[obs].vars[0], buf[obs].vars[1], buf[obs].vars[2], buf[obs].vars[3],
	      buf[obs].vars[4], buf[obs].vars[5], buf[obs].vars[6], buf[obs].vars[7], buf[obs].vars[8], 
	      buf[obs].vars[9], buf[obs].vars[10], buf[obs].vars[11] );
    }
  }

  return 0;
}