Re: Is there a way to use "pack" in pl/perl without resorting to pl/perlu?

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Tom Lane replied:
> My recollection is that they're intentionally excluded because they
> would otherwise be security holes --- there are some format codes that
> allow direct access to memory, or something like that.

They are not part of the standard "base core" opcode group, but part
of the "still_to_be_decided" group, because they can create and use
memory pointers. It's possible that they may someday get moved out
of this group, in which case they will suddenly start working :)

Herouth Maoz wrote:
> Anyway, I replaced the functionality with
> $content =~ s/([a-fA-F0-9]{2})/chr(hex($1))/eg;
> which seems to be doing the same thing as unpack( "H*", $content )

They are not doing the same thing, so be careful. :)

> I suspect it's less efficient than unpack, and I hope the function
> I created won't be too slow for use inside a trigger.

You should be fine with either one. While the unpack is indeed
around 3x faster, a simple s/// like the above still runs at over
220,000 times per second on my slow box, so I would not worry
about the speed. Remember in general to add a /o to the end of your
regex if the first part is constant to avoid unneeded recomplilation.

- --
Greg Sabino Mullane greg(at)turnstep(dot)com
End Point Corporation http://www.endpoint.com/
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