In July 2017 IBM has released the new Informix Fixpack 12.10xC9. 

Besides the usual bug fixes, Informix 12.10xC9 includes the new “Push Data Feature”. It is a Smart Trigger which enables the Informix database server to inform automatically and directly the application about changes in the database. The precondition is that trigger criteria have been defined in advance. This is done by simple SELECT statements and WHERE clauses. If changes in the database match with the defined criteria Informix “pushes” this information directly from the database server to the client. 

For those who would like to know more:

http://www.informixcommunity.com/blogs/introducing-informix-smart-triggers

Fix list for Informix Fix Pack 12.10xC9:

http://www-01.ibm.com/support/docview.wss?uid=swg27049826