Re: Sigh, my old HPUX box is totally broken by DSM patch

On Wed, Oct 23, 2013 at 11:35 AM, Stephen Frost <sfrost@snowman.net> wrote:
> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
>> I agree with Robert that it's odd and obnoxious that the call doesn't just
>> return with errno = ENOSYS.  However, looking in the archives turns up
>> this interesting historical info:
>> http://www.postgresql.org/message-id/25564.962066659@sss.pgh.pa.us
>
> Wow, well, good on HPUX for trying to run the code you told it to..
>
>> I wonder whether, if we went back to blocking SIGSYS, we could expect that
>> affected calls would return ENOSYS (clearly preferable), or if that would
>> just lead to some very strange behavior.  Other archive entries mention
>> that you get SIGSYS on Cygwin if the Cygwin support daemon isn't running,
>> so that's at least one place where we'd want to check the behavior.
>
> Would this make sense as a configure-time check, rather than initdb, to
> try blocking SIGSYS and checking for an ENOSYS from shm_open()?  Seems
> preferrable to do that in a configure check rather than initdb.

I don't see why.  It's a run-time behavior; the build system may not
be where the binaries will ultimately run.

-- 
Robert Haas
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