Re: postgresql in FreeBSD jails: proposal

Mischa Sandberg <mischa_sandberg(at)telus(dot)net> writes:
> Quoting Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
>> Mischa Sandberg <mischa_sandberg(at)telus(dot)net> writes:
>>> + if (kill(1,0) && errno == ESRCH && PGSharedMemoryIsInUse(0,NextShmemSegID))
>>> + continue;
>>
>> Isn't the last part of that test backward? If it isn't, I don't
>> understand what it's for at all.

> Serious blush here. Yes.

Actually, after re-reading what PGSharedMemoryIsInUse does, I don't
think you want to use it: it goes to considerable lengths to avoid
returning a false positive, whereas in this context I believe we
*do* need to avoid segments that belong to other data directories.
So you probably need a separate chunk of code that only does the
nattch test.

regards, tom lane