shared memory , semaphore help please!

Hi Guys,

I am facing great problem, have tried different methods now I m completely annoyed :'(.

I want to maintain the location on the memory accessed by all the sessions

I am working on some application where I m suppose to make communication among sessions. So I though of using semaphore(shared memory with mutual exclusion) in PHP.



I don't know why the script always create new memory location with same key when ever I open the page, instead it should maintain the pointer, with the value.

In example below, when ever I change the value for location "1234"(shmop_open(1234, "c", 0644, 1)) still the value remains one or I think php creates new location have same key("1234") with value one.

I think when ever I open the page it creates new thread, and every thread creates new location on the memory. I dont know how to stop this.

Example:
<?php

$shm_id = shmop_open(1234, "c", 0644, 1);


if(!$shm_id)
{
echo "Error while creating the shared memory segment.\n";
}
else
{
echo "Memory created";
}
$shm_bytes_written = shmop_write($shm_id, "1", 0);

if($shm_bytes_written != strlen("1"))
{
echo "Error while writing data\n";
}

$my_string = shmop_read($shm_id, 0, 1);
echo "....Value.... =". $my_string;
shmop_close ( $shm_id );
?>

(I can provide you with my attachment) please go through this.


Thanks
-Abhijit


Your help and new ideas will be appreciated.