example7-1.php	 example7-14.php  example7-3.php  example7-8.php
example7-10.php  example7-15.php  example7-4.php  example7-9.php
example7-11.php  example7-16.php  example7-5.php  testfile.txt
example7-12.php  example7-17.php  example7-6.php  testfile2.txt
example7-13.php  example7-2.php   example7-7.php