I\'m looking to implement a simple timer mechanism in C++. The code should work in Windows and Linux. The resolution should be as precise as possible (at least millisecond a
I found this which looks promising, and is extremely straightforward, not sure if there are any drawbacks:
https://gist.github.com/ForeverZer0/0a4f80fc02b96e19380ebb7a3debbee5
/* ----------------------------------------------------------------------- */
/*
Easy embeddable cross-platform high resolution timer function. For each
platform we select the high resolution timer. You can call the 'ns()'
function in your file after embedding this.
*/
#include <stdint.h>
#if defined(__linux)
# define HAVE_POSIX_TIMER
# include <time.h>
# ifdef CLOCK_MONOTONIC
# define CLOCKID CLOCK_MONOTONIC
# else
# define CLOCKID CLOCK_REALTIME
# endif
#elif defined(__APPLE__)
# define HAVE_MACH_TIMER
# include <mach/mach_time.h>
#elif defined(_WIN32)
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#endif
static uint64_t ns() {
static uint64_t is_init = 0;
#if defined(__APPLE__)
static mach_timebase_info_data_t info;
if (0 == is_init) {
mach_timebase_info(&info);
is_init = 1;
}
uint64_t now;
now = mach_absolute_time();
now *= info.numer;
now /= info.denom;
return now;
#elif defined(__linux)
static struct timespec linux_rate;
if (0 == is_init) {
clock_getres(CLOCKID, &linux_rate);
is_init = 1;
}
uint64_t now;
struct timespec spec;
clock_gettime(CLOCKID, &spec);
now = spec.tv_sec * 1.0e9 + spec.tv_nsec;
return now;
#elif defined(_WIN32)
static LARGE_INTEGER win_frequency;
if (0 == is_init) {
QueryPerformanceFrequency(&win_frequency);
is_init = 1;
}
LARGE_INTEGER now;
QueryPerformanceCounter(&now);
return (uint64_t) ((1e9 * now.QuadPart) / win_frequency.QuadPart);
#endif
}
/* ----------------------------------------------------------------------- */-------------------------------- */
The StlSoft open source library provides a quite good timer on both windows and linux platforms. If you want it to implement on your own, just have a look at their sources.
I am not sure about your requirement, If you want to calculate time interval please see thread below
Calculating elapsed time in a C program in milliseconds
STLSoft have a Performance Library, which includes a set of timer classes, some that work for both UNIX and Windows.
I highly recommend boost::posix_time library for that. It supports timers in various resolutions down to microseconds I believe
If one is using the Qt framework in the project, the best solution is probably to use QElapsedTimer.