#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#define PERMS 0666
int parse_args(int argc,  char *argv[ ], int* fd, int *np){
  if ((argc != 5) || 
      ((fd[0] = open(argv[1], O_RDONLY)) == -1) ||
      ((fd[1] = open(argv[2], O_RDONLY)) == -1) ||
      ((fd[2] = creat(argv[3], PERMS)) == -1) ||
      ((*np   = atoi(argv[4])) <= 0)){
    fprintf(stderr, "Usage: %s matrixA matrixB matrixC dimension\n", argv[0]);
    return(-1); };
  return 0;
}
int allocate_space(int** sp, int nproc){
  *sp = (int *) calloc(nproc, sizeof(int));
  if(*sp == NULL){
    perror("Calloc failed");
    return -1; 
  } else {
    return 0;
  }
}
int allocate_rows(int** A, int** B, int** C, int nproc){
  if(allocate_space(A, nproc) < 0) return -1;
  if(allocate_space(B, nproc) < 0) return -1;
  if(allocate_space(C, nproc) < 0) return -1;
  return 0;
}