Functions and triggers

Hopefully I can do what I want with a combination of functions and
triggers, the drawback being that I am coming from several years of
MySQL and know nothing about PostgreSQL functions or triggers. I
currently use msyslogd on linux to log syslog messages to a postgresql
database. I want to be able to do things - like send an email, etc... -
when certain messages are inserted into the database.

I have this for the table:

syslog=> \d syslogtb
               Table "syslogtb"
  Column  |          Type          | Modifiers
----------+------------------------+-----------
 facility | character(10)          |
 priority | character(10)          |
 date     | date                   |
 time     | time without time zone |
 host     | character varying(128) |
 message  | text                   |

syslog=>

And this is an example of the message field data:

%PIX-3-106011: Deny inbound (No xlate) udp src inside:10.10.1.160/1035
dst inside:10.29.0.45/161

How would I create and use a function/trigger to key on the PIX error
message code (%PIX-3-106011)?

Thanks in advance for your help

-Paul

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