Hi Curt, These are my open shared memories in the server output of ipcs command. ------ Shared Memory Segments -------- key shmid owner perms bytes nattch status 0x00000000 18645001 gOLeM 600 393216 2 dest 0x0000162e 18808842 root 666 30 1 The last one the the sharedmem the php will be using. the key is 5678 and as you said I have modified my code to $shm_id = shmop_open(intval($shm_key), "a",666,0) or die("FATAL ERROR:: $php_errormsg"); U obtain the shm_key from a file. The key I am using is 5678 and it is getting that value from the file. I even hardcoded the value, but the error is not getting solved. Is this a proble with any of the server configs? Coz we have downloaded an example C file and this is also not working with the PHP. Where as if the server and client both written in C are able to communicate using the shared memory. Any clue any one?? Ok...just a crazy query...does it have anything to do with Notice: import_request_variables(): No prefix specified - possible security hazard in which occurs due to register_globals set to Off?? On 11/16/05, Curt Zirzow <czirzow@xxxxxxxxx> wrote: > On Wed, Nov 16, 2005 at 03:33:22AM +0530, Yaswanth Narvaneni wrote: > > Hi! > > > > I have a server written in C++ and my webpages are in PHP. The PHP has > > to communicate with the server using shared memory. This was working > > fine on the server running FC-1 with php-4.3.8. We recently migrated > > to CentOS 4.1 (Equivalent to RHEL 4.1) running php-4.3.9. The error it > > displays is as follows: > > > > shmop_open(): unable to attach or create shared memory segment in > > /var/www/html/sharedmem.php on line 2 > > > > The server opens the shm in 666 (originally was 644) even then it was > > not working. I can see the shared mem open using 'ipcs' command. > > > > ... > > $shm_id = shmop_open($shm_key, "a",0,0) or die("FATAL ERROR:: Unable > > to Access Shared Memory"); > > You might want to try to open it within the same mode that the > server created it in: > > 1) > $shm_id = shmop_open($shm_key, "a",0666,0); > > 2) > are you 100% sure the key is valid? the error message you are > getting seems to point in this direction since the shmop_open is > failing on the C call to shmget(), wich usually fails when either > you dont have enough memory to create it (which you arn't doing), > some other creation problems, or that the key supplied wasn't > found. > > > Curt. > -- > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > > -- "In theory there is no difference between theory and practice. In practice there is." -- Fortune Cookie -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php