#include <unistd.h>
#include <fcntl.h>

main(int argc, char* argv[])
{
	char buf[512]={0};
	int i;
	int fd;

	if ((fd = open("output.cou", O_WRONLY|O_CREAT|O_TRUNC, 0666)) == -1)
	{
		perror(NULL);
		exit(1);
	}
		  
	for (i=0;i<5000;i++)
	{
		if (argc > 1)
		{
		     lseek(fd, 0, SEEK_END);
		}
		write(fd, buf, sizeof(buf));
	}
	close(fd);
}