PLS HELP

[nyihein]

Hi! I hope you can help me out here,
I've been trying to get a code that will
sends a signal of 0.5 secs, every hour
from 9am to 6pm
and then from 6pm onwards it resets back to 9am and restarts the whole process
do I use chrono?

[lastchance]

See
http://www.cplusplus.com/reference/thread/this_thread/sleep_for/
and
http://www.cplusplus.com/reference/thread/this_thread/sleep_until/

[Ganado]

edit:
It sounds like for your purposes, you don't care about millisecond precision, so I suggest using lastchance's methods, sleep_for and sleep_until. But I'll still keep my answer here for reference in case you want to do something similar to it.

original post:
I'm not sure if boost::asio is more accurate than std::thread's sleep_for, but here's an example of boost::asio with boost::posix_time (see first answer).
https://stackoverflow.com/questions/12904098/c-implementing-timed-callback-function

Also in that SO thread is someone giving an example using Win32 API's SetTimer function. I copied it and modified it to work on my Windows system:

#define STRICT 1 
#include <windows.h>
#include <iostream>

using namespace std;

VOID CALLBACK TimerProc(HWND hWnd, UINT nMsg, UINT_PTR idEvent, DWORD dwTime) 
{
    cout << "CALLBACK " << dwTime << endl;
}

int main(int argc, char *argv[], char *envp[]) 
{
    int Counter=0;
    MSG Msg;

    unsigned milliseconds = 2000;
    UINT TimerId = SetTimer(NULL, 0, milliseconds, &TimerProc); //2000 milliseconds

    cout << "TimerId: " << TimerId << '\n';
    if (!TimerId)
        return 16;

   while (GetMessage(&Msg, NULL, 0, 0)) 
   {
        ++Counter;
        if (Msg.message == WM_TIMER)
            cout << "Counter: " << Counter << "; timer message\n";
        else
            cout << "Counter: " << Counter << "; message: " << Msg.message << '\n';
        DispatchMessage(&Msg);
    }

    KillTimer(NULL, TimerId);
    return 0;
}

Edit 2:
Note there's a better way to handle GetMessage,
see https://msdn.microsoft.com/en-us/library/windows/desktop/ms644936(v=vs.85).aspx

[nyihein]

Thank You! it helped :)