Using external Apps from inside pgsql.

Hi Guys.. I'm just learning pgsql...

I'm attempting to interface pgsql to ImageMagick and am needing some
guidance..

ImageMagick has libraries which can be accessed with PERL, C, C++ (among
others and this is my order of preference)

Anyways, I'm finding the dox I have rather vague as to how to accomplish
this... My hope is to make a PL function which will update an image with
data.

PL/Perl doesn't seem to want to recognize the Image::Magick library include,
and I dont know how to make a func.so in C which uses IM and can be used
from inside PGSQL.

Any suggestions?

and another little question: any suggestions as to how to make a trigger
fire based on a time stamp expiring? (other than using a CRON job?) The
data for the image is time sensitive.

I'm usign 7.0.2 on FreeBSD 4.0

Thank-you,
Scott.