Thread: How can I get a REAL RANDOM number?

  1. #1

    Question How can I get a REAL RANDOM number?

    Hello, guys:

    How could I ger a REAL RANDOM NUMBER in C Programming?
    Don't ask me to call the rand(), it is not Real-Random, it is fake!
    If possible, please write down the source code.
    Thank you very much!
    CAUTION: Real-Random means generate one number in certain range everytime without any regulation!!

  2. #2
    Skunkmeister Stoned_Coder's Avatar
    Join Date
    Aug 2001
    A computer cannot think for itself. How can you tell a computer to pick a REAL random number. The best you will ever get is a pseudo-random number. You can vary the sequence of pseudorandom numbers produced by the rand() function by using srand() and seeding the generator with a different seed. If you are still insistent on going mad trying to do this then take a look at donald knuths art of computer programming vol.2 where he devotes a whole chapter to this problem.
    Free the weed!! Class B to class C is not good enough!!
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  3. #3
    Has a Masters in B.S.
    Join Date
    Aug 2001
    here is a really nice random number generator thats 4 time faster than rand and much more random...
    ADVISORY: This users posts are rated CP-MA, for Mature Audiences only.

  4. #4
    Registered User alex's Avatar
    Join Date
    Sep 2001

    If you are using linux, you could read "/dev/random" to get highly random numbers. But this can be quite slow (it is based on things like keyboard interrupts mouse interrupts, and network traffic; you can guess when it gets slow). But it's great for seeding good-quality pseudo-random generators!

    There's also a quicker version, called "/dev/urandom". This is based on the same principles as the generator of the url given by no-one, but it is reseeded regularly when there is enough data in the "/dev/random" pool.

    Some intel-chipsets have a built-in random number generator. (NOT kidding!).


  5. #5
    Registered User
    Join Date
    Oct 2001
    You can write a program which does make random numbers based on keyboard inputs (with getch()).

    You can make your normal random generator have a wider range:


    When I close my eyes nobody can see me...

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