Description:
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Since Postgresql 9.0, event notifications fired by the NOTIFY sql command includes a payload (a 8000 bytes max piece of text).

As of now, the PHP function pg_get_notify only retrieve the "channel" (name of the notification) and the backend pid.

The attached patch improves this situation by adding the payload to the returned array of the pg_get_notify function, when the connected PG backend version is at least 9.0.

Hope it helps...

Test script:
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$dbconn = pg_connect(...) ; // To be completed

pg_query($dbconn, "LISTEN toto");
pg_query($dbconn, "NOTIFY toto, 'Hello world !'");

$notify = pg_get_notify($dbconn, PGSQL_ASSOC) ;

print_r($notify) ;


Expected result:
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// Array("message" => "toto", "pid" => 12345, "payload" => "Hello world !")

Actual result:
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// Array("message" => "toto", "pid" => 12345)