Shouldn't there be a variable to pass to the rand function to give me number of bits ie rand(4).
Here is the info supplied about the rand function in the manual:
<pre> RAND
Synopsis

#include <stdlib.h>
int rand (void)

Description
The rand() function is a pseudo-random number generator. It returns an integer in the range 0 to
32767, which changes in a pseudo-random fashion on each call. The algorithm will produce a
deterministic sequence if started from the same point. The starting point is set using the srand() call.

The example shows use of the time() function to generate a different starting point for the sequence
each time.
Example
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
void main (void)
{
time_t toc;
int i;
time(&toc);
srand((int)toc);
for(i = 0 ; i != 10 ; i++)
printf("%dt", rand());
putchar(’n’);
}

See Also
srand()
Note
The example will require the user to provide the time() routine as one cannot be supplied with the
compiler. See time() for more detail.<pre/>