As Manual ....
============================================================
Example 18-2. Uploading multiple forms

  1 
  2 <form action="file-upload.html" method="post" enctype="multipart/form-data">
  3   Send these files:<br>
  4   <input name="userfile[]" type="file"><br>
  5   <input name="userfile[]" type="file"><br>
  6   <input type="submit" value="Send files">
  7 </form>
  8      
 
 


When the above form is submitted, the arrays $userfile, $userfile_name, and $userfile_size will be formed in the global scope (as well as in $HTTP_POST_VARS). Each of these will be a numerically indexed array of the appropriate values for the submitted files.

For instance, assume that the filenames /home/test/review.html and /home/test/xwp.out are submitted. In this case, $userfile_name[0] would contain the value review.html, and $userfile_name[1] would contain the value xwp.out. Similarly, $userfile_size[0] would contain review.html's filesize, and so forth.

============================================================

That's NOT TRUE....

For example , The FORM is..
============================================================
First - <input type=file name=img[]>
Second - <input type=file name=img[]>
============================================================

Script is below...
============================================================
echo count(img) is result 6 NOT 8.... -_-'

for ($i = 0;$i<count($img);$i++)
{
     echo img[$i]
}
is result 

img[0] = FILE_NAME OF FIRST FILE;
img[1] = FILE_TYPE OF FIRST FILE;
img[2] = FILE OF FIRST FILE;

img[3] = FIE_NAME OF SECOND FILE;
img[1] = FILE_TYPE OF SECOND FILE;
img[2] = FILE OF SECOND FILE;


AND 

echo img_name[0] is NULL...
echo img_size[0] is NULL...
echo img_type[0] is NULL...

INDEX [1] is too....

What's wrong.....?