UNIX Programming. struct timeval how to print it (C-programming)
In the GNU C Library, struct timeval
:
is declared in sys/time.h and has the following members:
long int tv_sec
This represents the number of whole seconds of elapsed time.
long int tv_usec
This is the rest of the elapsed time (a fraction of a second), represented as the number of microseconds. It is always less than one million.
So you will need to do
printf("%ld.%06ld\n", usage.ru_stime.tv_sec, usage.ru_stime.tv_usec);
to get a "nicely formatted" timestamp like 1.000123
.
Yes , timeval is defined like this
struct timeval {
time_t tv_sec;
suseconds_t tv_usec;
}
Using
printf ("%ld.%06ld\n", usage.ru_stime.tv_sec, usage.ru_stime.tv_usec);
will surely of help.
Since struct timeval
will be declared something like:
struct timeval {
time_t tv_sec;
suseconds_t tv_usec;
}
you need to get at the underlying fields:
printf ("%ld.%06ld\n", usage.ru_stime.tv_sec, usage.ru_stime.tv_usec);
printf ("%ld.%06ld\n", usage.ru_utime.tv_sec, usage.ru_utime.tv_usec);
yeah its
int main( void )
{
clock_t start, stop;
long int x;
double duration;
static struct timeval prev;
struct timeval now;
start = clock(); // get number of ticks before loop
for( x = 0; x < 1000000000; x++ );
// sleep(100);
stop = clock(); // get number of ticks after loop
// calculate time taken for loop
duration = ( double ) ( stop - start ) / CLOCKS_PER_SEC;
printf( "\nThe number of seconds for loop to run was %.2lf\n", duration );
gettimeofday(&now, NULL);
prev.tv_sec = duration;
if (prev.tv_sec)
{
int diff = (now.tv_sec-prev.tv_sec)*1000+(now.tv_usec-prev.tv_usec)/1000;
printf("DIFF %d\n",diff);
}
return 0;
}