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    std::random_device::random_device

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    std::random_device
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    random_device::random_device
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    random_device::operator()
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    <tbody> </tbody>
    explicit random_device(const std::string& token = /*implementation-defined*/ );
    		 (seit C++11)
    Erzeugt ein neues std::random_device Objekts, indem Verwendung des Arguments token, falls vorhanden, in der Implementierung definiert .
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    Constructs a new std::random_device object, making use of the argument token, if provided, in implementation-defined manner.
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    Typische Implementierung auf einem Linux-System, zum Beispiel erwartet token der Name eines Charakters Gerät, das Zufallszahlen erzeugt, wenn sie aus, mit dem Standardwert "/dev/urandom" lesen sein .
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    Typical implementation on a Linux system, for example, expects token to be the name of a character device that produces random numbers when read from, with the default value "/dev/urandom".
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    Ausnahmen

    Löst eine Implementierung definiert Ausnahmen von std::exception bei Ausfall abgeleitet .
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    Throws an implementation-defined exceptions derived from std::exception on failure.
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    Beispiel

    Demonstriert die zwei gängigen Arten von std::random_device auf Linux
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    Demonstrates the two commonly available types of std::random_device on Linux
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    #include <iostream>
#include <random>

int main()
{

    std::uniform_int_distribution<int> d(0, 10);

    std::random_device rd1; // uses /dev/urandom
    for(int n = 0; n < 10; ++n)
        std::cout << d(rd1) << ' ';
    std::cout << '\n';

    std::random_device rd2("/dev/random"); // much slower on Linux
    for(int n = 0; n < 10; ++n)
        std::cout << d(rd2) << ' ';
    std::cout << '\n';
}

    Output: 

    7 10 7 0 4 4 6 9 4 7 
2 4 10 6 3 2 0 6 3 7