On 9 October 2017 at 21:26, Abbas Butt <abbas.b...@enterprisedb.com> wrote: > Hi, > I am working on a contrib module that uses RegisterDynamicBackgroundWorker > API > to create a couple of worker processes. For synchronization between the > background worker processes I am using InitSharedLatch, SetLatch, WaitLatch > APIs. > One of the processes is supposed to wait for the latch, the other is > supposed to set it. > The system works perfectly fine as long as its run on Linux, however when > tried > on Windows, it fails giving the error: > ResetEvent failed: error code 6 > Error code 6 means invalid handle. Debugging reveals that the handle > contains > a valid value, however it seems that the handle is not accessible (was not > created) > in the process that is calling ResetEvent. > > Debugging the issue lead me to the following comment on top of > InitSharedLatch: > > * InitSharedLatch needs to be called in postmaster before forking child > * processes, usually right after allocating the shared memory block > * containing the latch with ShmemInitStruct. (The Unix implementation > * doesn't actually require that, but the Windows one does.) > > In my case this is not true, I am calling InitSharedLatch in _PG_init > which gets called at CREATE EXTENSION time. > My question : Is there a way to get the latches API work on windows > the way it is working on Linux?
I suspect you'd need to do it by having your extension load via shared_preload_libraries, registering its latch in shmem_startup_hook . But ... that's an off-the-cuff guess. -- Craig Ringer http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
