PRACE NPT

#include <stdlib.h>

#include <sys/types.h>

#include <sys/time.h>

/*  -------------------------------------------------------------------

    This function returns the wall clock time with micro seconds

    accuracy.

    The data type of the returned value is "double".

    The function can be called from a FORTRAN module. The value

    returned by cclock_ and cclock should be of type REAL(Kind = 8).

    -------------------------------------------------------------------

*/

double cclock_( void )

{

   const  double  micro = 1.0e-06;    /* Conversion constant */

   static long    start = 0L, startu;

   struct timeval tp;                       /* Structure used by gettimeofday */

   double         wall_time;          /* To hold the result */

   if ( gettimeofday( &tp, NULL) == -1 )

      wall_time = -1.0e0;

   else if( !start ) {

      start  = tp.tv_sec;

      startu = tp.tv_usec;

      wall_time = 0.0e0;

   }

   else

      wall_time = (double) (tp.tv_sec - start) + micro*(tp.tv_usec - startu);

   return wall_time;

}

double cclock( void )

{

   return cclock_();

}