gps_settime.c

This a support library and assorted sample programs for interfacing

#include "as_gps.h"
#include <time.h>
#include <sys/time.h>

void set_time(const AS_GPS_PositionData *pos);

int main(int argc, char **argv)
{
  if(as_gps_open("/dev/gps"))
  {
    printf("Can't open device\n");
    exit(1);
  }

  while(1)
  {
    void *data=NULL;
    double lat, lgt;
    unsigned read_count = 0;
    unsigned char result = as_gps_handle_input(&data);

    if(result == AS_GPS_RCV_POSITION_DATA) 
    {
      AS_GPS_PositionData *pos = (AS_GPS_PositionData *)data;

      if(pos->status > 0x0) // have atleast one sat
      {
        set_time(pos);
        exit(0);
      }
    }
    free(data);
  }

  as_gps_close(); 
}

void set_time(const AS_GPS_PositionData *pos)
{
  time_t time;
#if 0
  struct timeval timeval;
  struct timezone timezone;
#endif

  time = pos->time;

#if 0
  timeval.tv_sec = mktime(gmtime(&time));
  timeval.tv_usec = 0;

  timezone.tz_minuteswest = 0;
  timezone.tz_dsttime = 0;

#endif
#if 0
  if(settimeofday(&timeval, &timezone))
#else
  if(stime(&time))
#endif
  {
    printf("Error: Must be superuser to set time.\n");
    exit(1);
  }

  printf("Setting time to %s", asctime(localtime(&time)));
  printf("Setting time to %.24s UTC\n", asctime(gmtime(&time)));
}