stat_col(void)
{
    char fname[10+sizeof(long)*3];
    FILE *f = fopen((snprintf(fname, sizeof(fname), "/tmp/col%ld", (long)getpid()), fname), "w");
    fprintf(f, "collision: %d / %d (%6.2f)\n", collision.all, collision.total,
	    ((double)collision.all / (collision.total)) * 100);
    fprintf(f, "num: %d, str: %d, strcase: %d\n", collision.num, collision.str, collision.strcase);
    fclose(f);
}