/* File: makedata.c
   Make a file of random integers to test our
   sorting programs.
*/

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <time.h>

main(int argc, char *argv[]) {
   int i, r, n, *A ;
   long seed ;
   FILE *ofile ;

   /* Sanity check */
   if (argc != 3) {
      fprintf(stderr, "Usage: makedata n filename\n") ;
      exit(1) ;
   }

   /* Get number of items */
   r = sscanf(argv[1],"%d", &n) ;
   if (r != 1) {
      fprintf(stderr, "%s not an integer!\n", argv[1]) ;
      exit(1) ;
   }

   /* Open file */
   ofile = fopen(argv[2],"wb") ; 
   if (ofile == NULL) {
      printf("Could not open file: %s\n", argv[2]) ;
      exit(1) ;
   }
   
   /* Set random seed to time in seconds since 01/01/70 */
   seed = (long) time(NULL) ;
   printf("Set random seed to %ld\n", seed) ;
   srand48(seed) ;

   /* Allocate memory for our array */
   A = (int *) malloc(n * sizeof(int)) ;
   for ( i = 0 ; i < n ; i++) {
      A[i] = (int) lrand48() ;
   }

   r = fwrite(A, sizeof(int), n, ofile) ;
   if (r != n) {
      fprintf(stderr, "Oops, only %d numbers written\n", r) ;
   }
   fclose(ofile) ;
}