shmop_size
Description
int shmop_size ( int shmid)shmop_size() is used to get the size, in bytes of the shared memory block.
shmop_size() takes the shmid, which is the shared memory block identifier created by shmop_open(), the function will return and int, which represents the number of bytes the shared memory block occupies.
This example will put the size of shared memory block identified by $shm_id into $shm_size.