problems with flash + php counter

[fanto5k]

Hi,

I'm having problems getting a basic php counter to work on my site. I'm looking to have a small subtle flash movie at the bottom of my homepage (index.html) that shows the amount of visitors.

I've created a flash movie (PHPCounter.swf) with one frame. There is a dynamic text box with the variable name "Count". In the frame there is the actionscript:

loadVariablesNum ("PHPCounter.php", 0);

then I have a .php file (PHPCounter.php) with the following code:

<?
$filename = "PHPCounter.txt";
$fp = fopen( $filename,"r"); 
$Old = fread($fp, 100); 
fclose( $fp ); 
$Old = split ("=", $Old, 5);
$NewCount = $Old[1] + '1';
$New = "Count=$NewCount";
$fp = fopen( $filename,"w+");
if (flock($fp, 2)) { 
fwrite($fp, $New, 100); }
fclose( $fp ); 
print "Count=$NewCount";
?>

and finally a file PHPCounter.txt with:

Count=1

I've published the flash movie, added it to the homepage, uploaded all the files into the same root folder, and chmod both the php and text files to 666
Unfortunately the counter does not seem to be working, and no matter how many times I refresh the page it never goes past 2.

If anyone can give me some pointers on where I'm going wrong I'd be much obliged. The address is www.bonnieandclyde.biz.

Thanks,

Fanto.

[Musicman]

Hi,

I tried this script both on your server and on mine, in a way that would not hit the browser cache, and while the local copy works perfect, yours resets the counter quite often.
There is a potential problem with your script, but it should not cause problems unless you get to viewing rates ofmore than one visitor per minute (the script should open the file in r+ mode, lock it, and keep the lock until the end)
There is another problem that viewing again may take the value from browser cache rather than asking for a counter hit. This again can hardly explain the observed behaviour

Musicman

[fanto5k]

Hi Musicman,

Thanks for looking at the problem.

Unfortunately I'm a bit simple when it comes to php etc. Do you know if there is a way to solve this problem? Or do you have an alternative script that I might be able to use? As you can see I took the script from the tutorials on this site and just changed it a bit to suit myself because it wouldn't work for me.

Again, thanks for your time and any more help will be greatly appreciated.

Fanto.

[MyFriendIsATaco]

here is the counter code I use:

<?

$filename = "counter.txt";

$fp = fopen( $filename,"r"); 
$Old = fread($fp, 100); 
fclose( $fp ); 

$Old = split ("=", $Old, 5);

$NewCount = $Old[1] + '1';

$New = "varCount=$NewCount";

$fp = fopen( $filename,"w+");
if (flock($fp, 2)) { 
fwrite($fp, $New, 100); }
fclose( $fp ); 

echo ("varCount=$NewCount");

?>

then in flash, i use this code to retreive the data and make the hit...

function displayCounter(counter_url:String, counter_textbox:String) {
	var varphp:LoadVars = new LoadVars();
	var varcounter:LoadVars = new LoadVars();
	varphp.ran = random(999999);
	varphp.sendAndLoad(counter_url, varcounter, "GET");
	varcounter.onLoad = function(success) {
		if (success) {
			eval(counter_textbox)=varcounter.varCount;
		}
	};
}

and an example of using this would be:

displayCounter("counter.php", "Count");

and that would load 'counter.php' and display its contents in the textfield 'Count'

[Musicman]

Hi,

you are already taking care of the cache with that random piece.
Nowm the proper sequence of events for updating a file would be

$fp = fopen($filename, "r+"); // open for read, later write
flock($fp, LOCK_EX); // wait until we have the file for ourseleves
$old = fread($fp, 100); // read data
Now, at this point dont close the file !!
Rather, later:
fseek($fp, 0, 0); // set file position to start
fputs($fp, $new); // save new data
fclose($fp); // finished - this will release the lock

As I said before, this will help against a common problem of concurrent access (and despite statistics this kind of problem even happened with a guestbook receiving less than 10 entries a day)
I dont know how frequented your site really is, but in order for this collision to happen a few times per minute, you would need really many, many visitors (or maybe some silly flash script that requests the counter at its frame rate )

Musicman