Use srand() twice in a function?

Can I use the srand() function twice in a function like so?

Code:

---

void delaycalc(void)
{
    int one;
    int result;
   
    srand((unsigned)time(NULL));
    one = rand();
   
    srand(one);
    result = rand() % 1200;
   
    printf("%i", result);
}

---

You see I'm trying to get random numbers that are 1200 or less. However, when I use the time function to make a seed and loop the function so it displays 20 random numbers, it increments slowly like 2390, 2394, 2398 etc.

So it's hardly random. So can I use two srand() functions to try and randomise it more (Preferably so the values move down sometimes aswell)?

Quote:

---

Originally Posted by Jake.c

You see I'm trying to get random numbers that are 1200 or less. However, when I use the time function to make a seed and loop the function so it displays 20 random numbers, it increments slowly like 2390, 2394, 2398 etc.

---

You could... wait longer before running the program again :)

Prelude suggests that you hash the value returned by time(). For an example, read her article on using rand().

you should not use srand twice - it will descrease the randomness of your results, not increase them

Check the http://www.eternallyconfuzzled.com/a..._art_rand.aspx about more info

Now I have the problem of the function that the eternally confused tutorial gives at the end. When I try to compile it says:

Code:

---

unsigned readySeed()
{
        time_t now = time ();
        unsigned char *p = (unsigned char *)&now;
        unsigned seed = 0;
        size_t i;
 
        for ( i = 0; i < sizeof now; i++ )
            seed = seed * ( UCHAR_MAX + 2U ) + p[i];
 
 return seed;
}

---

`UCHAR_MAX' undeclared (first use in this function)

You need to #include <limits.h>

Oh thankyou very much!