Are longer sleeps (in C++) less precise than short ones

Question

I have a task to do something every \"round\" minute(at xx:xx:00) And I use something like

const int statisticsInterval=60;
    time_t t=0;
    while (1)
            


        

Answer 1

If the goal is to sleep until a given system time (xx:xx:00), consider using the overload of boost::this_thread::sleep that takes a time, as in boost::posix_time::ptime, rather than a duration.

for example,

#include 
#include 
#include 
int main()
{
    using namespace boost::posix_time;
    ptime time = boost::get_system_time();
    std::cout << "time is " << time << '\n';
    time_duration tod = time.time_of_day();
    tod = hours(tod.hours()) + minutes(tod.minutes() + 1);
    time = ptime(time.date(), tod);
    std::cout << "sleeping to  " << time << "\n";
    boost::this_thread::sleep(time);
    std::cout << "now the time is " << boost::get_system_time() << '\n';
}

in C++0x these two overloads were given different names: std::this_thread::sleep_for() and std::this_thread::sleep_until();