The way I have always used is:
srand ( time(0) );
var = (int) (rand() / (RAND_MAX + 1.0) * (high - low + 1);
Example:
Code:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main()
{
int randnum, high, low, num, i;
srand( time(0) );
printf("Please enter the range (example 1 - 20): ");
scanf("%d - %d",&low,&high);
printf("\nHow many number do you wish to get?: ");
scanf("%d",&num);
for (i = 0;i < num;i++)
{
randnum = (int) (rand() / (RAND_MAX + 1.0) * (high - low + 1) + low);
printf("\n%d",randnum);
}
return 0;
}