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crandomsrandrandom-seed

Srand with char array in C?

How can I random seed with a char array instead of an int in C?
I want to use a password, not a number, but srand only takes integers.
Is there a way to do this?

Solution

  • Just use a hash function. A classic is hash_pjw,

    unsigned hash_pjw (const void *str)   
{
  const char *s = str;
  unsigned int g, h = 1234567u;
  while (*s != 0) {
    h = (h << 4) + *s++;
    if ((g = h & (unsigned int) 0xf0000000) != 0)
       h = (h ^ (g >> 24)) ^ g;
  }
  return h;
}

    Note that rand() is nothing like cryptographically secure.