Generating random permutations

/* randompermute.c - A program will generate "random permutations of n elements"
if at all points the n! possible permutations have all the same probability 
of being generated.
*/

#include <stdio.h>
#include <stdlib.h>

// It returns a random permutation of 0..n-1
int * rpermute(int n) {
int *a = malloc(n*sizeof(int));
int k;
for (k = 0; k < n; k++)
a[k] = k;
for (k = n-1; k > 0; k--) {
int j = rand() % (k+1);
int temp = a[j];
a[j] = a[k];
a[k] = temp;
}
return a;
}

// Print a 8 elements per line
void printarray(int n, int a[n]) {
int k = 0;
for (k = 0; k < n; k++) {
printf("%6d   ", a[k]);
if (k % 8 == 7)
printf("\n");
} 
}

int main(void) {
int limit = 6;
int *a;
int k;
// Print 7 permutations
for (k = 0; k < 7; k++) {
a = rpermute(limit);
printarray(limit, a);
printf("\n");
}

return 0;
}