How do we get the actual pgproc object from the

SHMEM_OFFSET proc /* link to pgproc of owning backend*/ in the PROCLOCKTAG struct in file Lock.h

The same question also for SHMEM_OFFSET lock /*link to per-lockable-object information*/ in the same struct

Is SHMEM_OFFSET a pointer to an address which has the "header" of the unique pgproc object? '

So, again, how to get the actual PGPROC and LOCK object from SHMEM_OFFSET?

Any help will be greatly appreciated,

Thanks,

Sumaira