windows - How are command prompt random numbers generated? -


in command prompt environment, there variable %random% uses algorithm generate pseudo-random numbers.

does know algorithm generates these numbers?

the %random% dynamic variable generates random number 0 32,767 inclusive. algorithm of these numbers generated this:

srand((unsigned)time(null));

it turns out windows command processor uses standard naïve algorithm seeding random number generator (quote here)

it spits out new number every second because of time seed.

as dbenham pointed out, 2 command prompts opened in same second output same exact numbers because of pseudorandomness , taking in of time seed.


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