main.c

#include <stdio.h>

void split(char *bigbuffer, int bufSize) {
  int index = 0;

  while (index < bufSize) {
    bigbuffer[index + 5] = 0;
    printf("%s\n", bigbuffer + index);
    printf("---- separation ---\n");
    index += 6;
  }
}

int main(int argc, char *argv[])
{
  char bigbuffer[] = "aaaaa\naaaab\naaaac\n";
  split(bigbuffer, sizeof(bigbuffer));
  return 0;
}