THECOUNTER

[Anon]

Hi!!!!!!!!!!

[Anon]

Hi..
Try this.....
Create counter txt....( write 0)
Chmod 777...
cod is...
<?

$Counterfile = "counter.txt";

function showcounter($Counterfile ) {
$fp = fopen($Counterfile ,rw);
$num = fgets($fp,5);
$num += 1;
print "Counter: $num ";
exec( "rm -rf $Counterfile ");
exec( "echo $num > $Counterfile ");
}

if (!file_exists($Counterfile )) {
exec( "echo 1 > $Counterfile ");
}
showcounter($Counterfile );

?>

[kparker]

You came up with all that in response to "hi!"?????? I'm impressed!
(So much that I won't even do my usual and point out that it's not
multi-user safe...)

[[deleted]]

Hello!!!!!!

( wonder what Nightmarex has to say about that! :-) )

[lth2h]

Kirk Parker wrote:

... it's not
multi-user safe....

Ok. I'm stupid. Why isn't it multi-user safe? I use something very similar. What changes do I need to make?

Thanks

[Anon]

Because it opens a file without locking.
So if two users run the script... first come-first serve.

[kparker]

Well, since you asked.... :-)

It's not safe because any number of users can end up trying to update it at the same time, leading to non-deterministic results.

To be safe/accurate, the file needs to be locked. As an additional bonus, the following code will do all the updating with a single file open, so the lost efficiency due to the lock will be at least partly offset be eliminating the overhead of the two (!) exec's:

function get_next_counter_value($Counterfile )
{
$fp = fopen($Counterfile, "r+"); // + is key here: update mode lets us write too

flock($fp, 2 );

$num = fgets($fp,10) + 1; // allow more the 99999 hits
rewind($fp);
fwrite( $fp, printf("%d", $num ));

flock($fp, 3 );

return $num;
}