Re: CustomScan support on readfuncs.c

On Fri, Nov 6, 2015 at 2:02 AM, Kouhei Kaigai <kaigai@ak.jp.nec.com> wrote:
> I tried to split the previous version into two portions.
>
> - custom-scan-on-readfuncs.v2.patch
> It allows to serialize/deserialize CustomScan node as discussed upthread.
> Regarding of get_current_library_filename(), I keep this feature as
> the previous version right now, because I have no good alternatives.

Why can't the library just pass its name as a constant string?

> In this patch, the role of TextReadCustomScan callback is to clean out
> any tokens generated by TextOutCustomScan. The CustomScan node itself
> can be reconstructed with common portion because we expect custom_exprs
> and custom_private have objects which are safe to copyObject().

Some of the documentation changes for the embed-the-struct changes are
still present in the readfuncs patch.

Rather than adding TextReadCustomScan, I think we should rip
TextOutputCustomScan out.  It seems like a useless appendage.

-- 
Robert Haas
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