clock

This is a discussion on clock within the C++ Programming forums, part of the General Programming Boards category; I want to make a clock in realtime, but every time I print out a new time it never updates, ...

  1. #1
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    clock

    I want to make a clock in realtime, but every time I print out a new time it never updates, how come?

    Timer.h
    Code:
    #ifndef _TIMER_
    #define _TIMER_
    
    #include <ctime>
    
    
    class Timer {
        clock_t counter;
    public:
        Timer(): counter(0) {};
    
        bool elasped(clock_t ms)
        {
            clock_t tick = std::clock();
    
            if(tick - counter >= ms)
            {
               counter = tick;
        return true;
    		}
    		return false;
    	}
    };
    #endif
    main.cpp file
    Code:
    int main()
    {
    	Timer timer;
    	time_t now;
    	time(&now);
    
    	while(true)
    	{
    		if(timer.elasped(1000))
    			cout << ctime(&now);
    	}
    }

  2. #2
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    You're never updating the variable now inside the while loop. Do something like...
    Code:
    	while(true)
    	{
                    time(&now);
    		if(timer.elasped(1000))
    			cout << ctime(&now);
    	}

  3. #3
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    What exactly did time(&now) do in the while(true) ??

    because it works.

    Thx scwizzo

  4. #4
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    ctime() just converts a time that was already retrieved to a string. time() retrieves that time. So essentially you were retrieving the time once, then printing the same thing over and over. Putting it in the while loop makes it gather a new time every pass of printing it.

  5. #5
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    Update the variable now, as scwizzo noted you did not do.
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  6. #6
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    Aaah I see, thanks for all the answers =)

  7. #7
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    You probably want to:
    1. Update now AFTER the time has elapsed.
    2. Spell elaPSed correctly.
    3. Use CLOCKS_PER_SEC to calculate milliseconds, as "clock()" may return something that isn't milliseconds.

    Further, if you want to wait for a second, you should probably not "eat" all the CPU time for that period of time. Sleep() in Windows will wait for a specific number of milliseconds, and usleep() in Linux/Unix will wait for a specific number of microseconds.

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  8. #8
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    aight matsp.

    but try for yourself with the spelling thingy.

    when printing out timer. the compiler suggest elasped, so.. not my fault ;D

  9. #9
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    Quote Originally Posted by And3rs View Post
    aight matsp.

    but try for yourself with the spelling thingy.

    when printing out timer. the compiler suggest elasped, so.. not my fault ;D
    That's because elasped is defined with the wrong name in the timer class itself. Fix that, and it should fix the rest.

    I know my spelling is not perfect (mostly because my fingers do not do what I think they are doing), but having incorrect spelling for names in your program just makes it really annoying, because I would write "timer.elapsed", and then wonder why I get a compiler error.

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  10. #10
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    Ah yeah, I saw where my typo was now.

    Thanks for the correction

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