Re: OidFunctionCall* returning null. - Mailing list pgsql-hackers

From David Zwarg
Subject Re: OidFunctionCall* returning null.
Date
Msg-id CANSnHN2myL+fOq5T=zovxNM3DOgy1WALXvZkjSD1fjS0r1=A0Q@mail.gmail.com
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In response to OidFunctionCall* returning null.  (David Zwarg <dzwarg+postgis@azavea.com>)
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I just found this thread:

http://archives.postgresql.org/pgsql-general/2011-11/msg00424.php

So I'll use the same workaround.

Nothing to see here, folks, move along....

d

On Fri, Nov 18, 2011 at 11:17 AM, David Zwarg <dzwarg+postgis@azavea.com> wrote:
Hello,

I have been working with the PostGIS developers, and I'm implementing a facility to use 'callback' functions to process cells in a raster image.

I have implemented this behind the scenes as a C function that calls a provided sql regprocedure with OidFunctionCall*. I have been reading the docs, and it states that "Note that neither arguments nor result are allowed to be NULL."

In this use case, there are legitimate reasons to return NULL from a 'callback' function -- is there an alternative method that I should use, instead of OidFunctionCall*?

Thanks,
David

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