process shared mutexes?

[Volker Lendecke]

Hello!

For Samba's tdb I'm trying to get process shared robust mutexes to
work. However, tdb has a usage pattern that seems to confuse FreeBSD
11 (32-bit x86 if that matters).

The attached program fails in the final pthread_mutex_lock call. If I
comment out the call to

ptr = mmap(NULL, 0xb0, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0x1000);

it works.

FWIW, tdb uses robust shared mutexes on Linux successfully for a while
now. I haven't tried Solaris yet, the only other platform I know about
that has them.

What am I doing wrong?

Thanks,

Volker