[mythtv-users] Mythzoneminder and mmap
Paul Harrison
mythtv at sky.com
Sat Oct 20 22:34:40 UTC 2012
On 20/10/12 21:42, Greg Grotsky wrote:
> Thanks Paul! I added an #endif and it compiled. I ran it and I see
> this in the mythzmserver.log
>
> loading zm config from /etc/zm.conf
> ZM is version '1.25.0'
> Listening on port: 6548
> _POSIX_MAPPED_FILES is defined and set to 200809
> Failed to shmget for monitor: 2
>
> So the zm server sees that I have memory mapped files but still tries
> to use shared memory, right?
>
Yep of cause you need the #endif sorry about that.
That looks correct so it's not that. I take it at no point do you see
something like 'Opened mmap file: /dev/shm/zm.mmap.2' in the log? Do you
see something like this earlier in the log 'Memory path directory is:
/dev/shm'? You will need to use -v to see those messages.
If the memory path looks correct the next thing to look at would be the
open() call in ZMServer::initMonitor(). The user running mythzmserver
will require read permissions on the mmap file which will be at
/dev/shm/zm.mmap.2 if the example you gave earlier is correct.
I did spot a bug in that code but I can't see how it would cause the
problem you are seeing though. The call to mmap() will return MAP_FAILED
not NULL that the code is assuming at the moment but that would more
than likely cause a segfault later on.
Paul H.
More information about the mythtv-users
mailing list