Does Synchronization work properly in file handling in php?

[tushar deshpande]

hello,
i have prepared a php file for visitcount. that creates a text file per

day. as soon as any user visits that page ,a counter is incremented. but on

my site there is lots of trafic. that's why counter again starts with zero

. and file also written to null.b'coz multiple users(abt 1 to 10 lakh) can

visit page at same time.

so i want to know if code is right then what is the problem?
how can we solve this proble? is there any locking file mechanism in php?
code :

 $count_path = "../count_visit/".date("d-m-Y").".txt";
 
       if(file_exists($count_path))
       {
        $handle = fopen($count_path, 'r');
                    $read_count= fread($handle, filesize($count_path));     
 
 
                    fclose($handle);
              /* or used    $read_count = file_get_contents($count_path);
              */         
                   if($read_count <> '' )
                   {
                       $inc_count = (int)$read_count + 1;
                       $handle = fopen($count_path, 'w');
                       fwrite($handle, $inc_count);
                       fclose($handle);  
                    }
                 }
                 else
       {
                      // executes when any user visits first time
                      $handle = fopen($count_path, 'w');
                       fwrite($handle, '1' );
                      fclose($handle);
        }

Plz solve this problem.

[pbmods]

Heya, Tushar.

Please use CODE tags when posting source code. See the REPLY GUIDELINES on the right side of the page next time you post.

[ak1dnar]

Moving thread from Php Articles section to the Forum.
-ajaxrand

[pbmods]

Heya, Tushar.

Check out flock().

[kovik]

File-locking may give you unexpected results when multiple visitors come, as some of them will be disenfranchised.

If you have access to a database, you could do this very easily there, as it accounts for multiple queries within itself.