Re: [PATCH] Add SIGCHLD catch to psql

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Stephen Frost <sfrost@snowman.net>
Cc: Robert Haas <robertmhaas@gmail.com>, David Fetter <david@fetter.org>, Bruce Momjian <bruce@momjian.us>, pgsql-hackers@postgresql.org
Date: 2010-05-16T16:22:33Z
Lists: pgsql-hackers
Stephen Frost <sfrost@snowman.net> writes:
> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
>> A saner
>> approach, which would also help for other corner cases such as
>> out-of-disk-space, would be to check for write failures on the output
>> file and abandon the query if any occur.

> I had considered this, but I'm not sure we really need to catch *every*
> write failure.  Perhaps just catching if the '\n' at the end of a row
> fails to be written out would be sufficient?

If you're combining this with the FETCH_COUNT logic then it seems like
it'd be sufficient to check ferror(fout) once per fetch chunk, and just
fall out of that loop then.  I don't want psql issuing query cancels
on its own authority, either.

			regards, tom lane